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- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now something interesting happens as you go to the d block . we studied this when we looked at electron configurations , but if you look at the electron configuration for say scandium right over here , the electron , let me do it in magenta , the electron configuration for scandium , so scandium , scandium 's electron ...
and how would electron configurations work with the previous labeling.. ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
that 's because the elements in a column , or the elements in a group tend to have the same number of electrons in their outermost shell . they tend to have the same number of valence electrons . and valence electrons are electrons in the outermost shell they tend to coincide , although there 's a slightly different va...
why do elements on different rows have an equal number of valence electrons as each other ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15 , 16 , 17 , and 18 . as some of ya 'll might be thinking , what about these f block elements over here ? if we were to properly do the periodic table w...
what is s , p , d , f ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then it 's going to go 3s1 . once again , it has one valence electron , one electron in its outermost shell . all of these elements in orange right over here , they have one valence electron and they 're trying to get to the octet rule , this kind of stable nirvana for atoms .
how do you know what electron configuration is the same as one of the elements ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let me emphasize that . we 're backfilling the d block . but these , their outermost electrons are in ...
what is d block and p block ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
if we move one over to the right this group two right over here , these are called the alkaline earth metals . alkaline , alkaline earth metals . once again , they have very similar ...
what is an alkaline metal ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
in my textbook there '' s written that there are 8 groups in the periodic table ... ... how come 18 groups ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now something interesting happens as you go to the d block . we studied this when we looked at electron configurations , but if you look at the electron configuration for say scandium right over here , the electron , let me do it in magenta , the electron configuration for scandium , so scandium , scandium 's electron ...
how do the inner electron influence the property ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why alkali 'earth ' metals ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
so what is the main difference between alkali metals and alkaline earth metals ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
is it only that alkaline earth metals are less reactive than alkali metals or there is something else too ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let 's just think a little about some of the groups that you will hear about and why they react in very similar ways . if we go with group one , group one ... and hydrogen is a little bit of a strange character because hydrogen is n't trying to get to eight valence electrons . hydrogen in that first shell just wants to...
at the time 0 , why did n't you circle the hydrogen element because they are in the same group ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then we start filling the d block . these are the d block elements here . you have to remember , the d block you backfill .
i want to learn the properties of all the elements of p block ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15...
how come hydrogen is in group 1 when in most cases it does not share the same properties as the other group 1 elements ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let me write this out , alkaline earth metals . but for them it 's easier to lose two electrons than to try to gain six to get to eight . and so these tend to also be reasonably reactive and they react by losing those two outer electrons .
so the reason why some elements lose their electron is because is easier to lose electrons then to gain electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
why are gasses elements on the periodic table ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
so 2p2 . how many valence electrons does it have ? well , in its second shell , its outermost shell , it has two plus two .
how should i know how many valence electrons each elements have ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
the groups in the periodic table show how many electrons are in the outer layer ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
why do they have very similar properties ? well , to think about that you just have to think about their electron configurations . for example , the electron configuration for lithium is going to be the same as the electron configuration of helium , of helium . then you 're going to go to your second shell , 2s1 .
for example : h , li , na , k , rb , cs , fr all have 1 electron in the outer layer ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
so 2p2 . how many valence electrons does it have ? well , in its second shell , its outermost shell , it has two plus two .
and so on ... or do the number in the boxes tell how many electrons are in the outer layer ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15...
why is hydrogen put in 1st group than in 17th group ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now something interesting happens as you go to the d block . we studied this when we looked at electron configurations , but if you look at the electron configuration for say scandium right over here , the electron , let me do it in magenta , the electron configuration for scandium , so scandium , scandium 's electron ...
is n't scandium supposed to have the electron configuration of krypton and not argon ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why do alkali metals react with water ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then you 're going to go to your second shell , 2s1 . it has one valence electron . it has one electron in its outermost shell . what about sodium ? well , sodium is going to have the same electron configuration as neon . then it 's going to go 3s1 .
for example sodium has 1 electron , be 2 , sc 3 , ni 1 , zn 12 , and so on ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
how many electrons does it have in its outermost shell ? once again its outermost shell is its fourth shell , is its fourth shell . these are , you could argue , higher energy electrons that fills this ...
what 's the difference betweeen orbit and shell ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
how many electrons does it have in its outermost shell ? once again its outermost shell is its fourth shell , is its fourth shell . these are , you could argue , higher energy electrons that fills this ...
are s orbit and k shell same thing ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
5 , why is sc equal to ar ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
why does there have to be a gap ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
what are alkali metals and halogens ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them .
how long did it take to create the periodic table of elements ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15...
why are the 15th group elements are called pnictogens ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
1st group is for alkali metals than why is hydrogen placed in the 1st group ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
if we move one over to the right this group two right over here , these are called the alkaline earth metals . alkaline , alkaline earth metals . once again , they have very similar ...
why berillium not considered as alkaline earth metal ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
we could keep going on , for example , oxygen and sulfur . these would both want to take two electrons from someone else because they have six valence electrons and they want to get to eight . they have similar bonding behavior .
why would the group 2 metals want to give up their electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
we could keep going on , for example , oxygen and sulfur . these would both want to take two electrons from someone else because they have six valence electrons and they want to get to eight . they have similar bonding behavior .
also , why does everyone want 8 valance electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
that 's because the elements in a column , or the elements in a group tend to have the same number of electrons in their outermost shell . they tend to have the same number of valence electrons . and valence electrons are electrons in the outermost shell they tend to coincide , although there 's a slightly different va...
what 's the difference between 8 and every other number ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
well , in its second shell , its outermost shell , it has two plus two . it has four valence electrons . that 's going to be true for the things in this group .
why does n't sc have 3 valence electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why is francium most reactive in alkali metals ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then you 're going to go to your second shell , 2s1 . it has one valence electron . it has one electron in its outermost shell .
why does potassium have 1 valence electron and not 9 ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
they tend to have the same number of valence electrons . and valence electrons are electrons in the outermost shell they tend to coincide , although there 's a slightly different variation . the valence electrons , these are the electrons that are going to react , which tend to be the outermost shell electrons , but th...
if you add up the electrons , it 's third shell can hold up to 18 electrons , so would n't the remaining nine go there ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why do some element numbers differentiate from their groups like `` alkali metals '' or stuff like that ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
we could keep going on , for example , oxygen and sulfur . these would both want to take two electrons from someone else because they have six valence electrons and they want to get to eight . they have similar bonding behavior .
why does carbon want to gain eight electrons in the ch4 methane molecule ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
once you 've kind of backfilled those d blocks then you come over here and you start filling the p block . for example , if you look at the electron configuration for , let 's say carbon , carbon is going to have the same electron configuration as helium , as helium . then you 're going to fill your s block , 2s2 , and...
carbon is described to have same configuration to helium , but then he says that carbon has 4 valence electrons or valency 4. how can it be similar to helium ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
well , in its second shell , its outermost shell , it has two plus two . it has four valence electrons . that 's going to be true for the things in this group .
is there a difference between configuration and valence electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let me emphasize that . we 're backfilling the d block . but these , their outermost electrons are in ...
does backfilling give them more energy potential when they do react or what properties does backfilling give the element ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
in fact , they especially love to react with the alkali metals over here . then finally you get to kind of your atomic nirvana in the noble gases here . the noble gases , that 's the other name for the group , 18 elements , noble gases . they all have the very similar property of not being reactive .
what 's the difference between noble gases and halogens ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
so 2p2 . how many valence electrons does it have ? well , in its second shell , its outermost shell , it has two plus two .
what are groups and how many are there ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
what 's the difference between alkali metals and alkali earth metals ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
but for them it 's easier to lose two electrons than to try to gain six to get to eight . and so these tend to also be reasonably reactive and they react by losing those two outer electrons . now something interesting happens as you go to the d block .
how come carbon has 4 electrons on its outer row ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
they all have the very similar property of not being reactive . why do n't they react ? because they have eight valence electrons .
is n't the row farthest out the `` p '' row ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then we start filling the d block . these are the d block elements here . you have to remember , the d block you backfill .
what are the blocks of elements ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
because they 're so reactive it 's hard to find them where they have n't reacted with other things . let 's keep looking at the other groups . if we move one over to the right this group two right over here , these are called the alkaline earth metals . alkaline , alkaline earth metals .
so there are 18 groups right ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then you 're going to go to your second shell , 2s1 . it has one valence electron . it has one electron in its outermost shell .
what does , '' valence , '' mean ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
group one , if you put hydrogen aside , these are referred to as the alkali metals . and hydrogen is not considered an alkali metal . these right over here are the alkali .
why is hydrogen not considered an alkali metal ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
they tend to have the same number of valence electrons . and valence electrons are electrons in the outermost shell they tend to coincide , although there 's a slightly different variation . the valence electrons , these are the electrons that are going to react , which tend to be the outermost shell electrons , but th...
why do atoms need 8 electrons in their outer energy shell to become stable ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let me emphasize that . we 're backfilling the d block . but these , their outermost electrons are in ...
keep thinking about backfill.. what does backfilling d-block really means ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
let me emphasize that . we 're backfilling the d block . but these , their outermost electrons are in ...
in sc , does it mean electrons are filled at the d-block first rather than s-block which is lower energy level ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these would both want to take two electrons from someone else because they have six valence electrons and they want to get to eight . they have similar bonding behavior . you go to this yellow group right over here .
why do 113 , 115 , 117 , and 118 have similar names ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then we start filling the d block . these are the d block elements here . you have to remember , the d block you backfill . in the d block , this is going to be now 3s1 .
why do we have to backfill the `` d-block '' ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15...
why do elements in group 2 has a lower melting and boiling points as its atomic sizes increases ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
they all have the very similar property of not being reactive . why do n't they react ? because they have eight valence electrons .
are n't 4s and 3d right next to each other in terms of energy levels ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then you 're going to go to your second shell , 2s1 . it has one valence electron . it has one electron in its outermost shell .
how does li have the same electron configuration of he if the first group has 1 valence electron and the group 18 has 8 valence electrons ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
group one , if you put hydrogen aside , these are referred to as the alkali metals . and hydrogen is not considered an alkali metal . these right over here are the alkali .
why is hydrogen not called a alkali metal ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
there , once again , are exceptions in these transition metals right here that for the most part are going in backfilling that d block . once you 've kind of backfilled those d blocks then you come over here and you start filling the p block . for example , if you look at the electron configuration for , let 's say car...
what is p , b and d blocks ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why do we need to know about the alkali metals , alkaline earth metals , noble gases ... ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
it does n't share as much in common with everything else in group one as you might expect for , say , all of the things in group two . group one , if you put hydrogen aside , these are referred to as the alkali metals . and hydrogen is not considered an alkali metal . these right over here are the alkali .
why do hydrogen is considered as group 1 elements ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
well , in its second shell , its outermost shell , it has two plus two . it has four valence electrons . that 's going to be true for the things in this group .
why dont the transition metals ' valence electrons automatically start backfilling the d block ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
these right over here are the alkali . alkali metals . now why do all of these have very similar reactions ?
why does hydrogen is with the alkali metals ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth , seventh , eighth , group nine , group 10 , 11 , 12 , 13 , 14 15...
why group 17th elements are called halogens ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
now something interesting happens as you go to the d block . we studied this when we looked at electron configurations , but if you look at the electron configuration for say scandium right over here , the electron , let me do it in magenta , the electron configuration for scandium , so scandium , scandium 's electron ...
what exactly is electron configuration ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
then we start filling the d block . these are the d block elements here . you have to remember , the d block you backfill .
why are the transitional elements not classfied into groups ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
once you 've kind of backfilled those d blocks then you come over here and you start filling the p block . for example , if you look at the electron configuration for , let 's say carbon , carbon is going to have the same electron configuration as helium , as helium . then you 're going to fill your s block , 2s2 , and...
how can you say that scandium has the same electronic configuration as argon and carbon has the same as helium ?
- let 's talk a little bit about groups of the periodic table . now , a very simple way to think about groups is that they just are the columns of the periodic table , and the standard convention is to number them . this is the first column , so that 's group one , second column , third group , fourth , fifth , sixth ,...
if we move one over to the right this group two right over here , these are called the alkaline earth metals . alkaline , alkaline earth metals . once again , they have very similar ...
what is the difference in between `` alkali '' and `` alkaline '' ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
let me do it in different color . dr looks something like that . so that is f. and so the dot product of these two says , ok , how much of f is going in the same direction as dr ?
what is the difference between ds and dr ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
but when you 're dealing with the scalar field , we saw on the last video , we saw that it does n't matter which direction that you traverse the path in . that the positive path has the same value as the negative path . and that 's just because we 're just trying to find the area of that curtain .
is it plausible to think of dependence of path direction as swimming with ( positive ) or against ( negative ) a current ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
x prime of t i plus y prime of t j . and then all of that times the scalar dt . this 'll be a scalar value , and then we 'll have another scalar value of dt over there . now , what is this going to be equal to if i take this reverse integral ?
is n't a scalar simply a vector with a single dimension ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
this is just a vector field over the x-y plane . how the line integral of this vector field , of this vector field over this path , compares to the line integral the same vector field over that path . how that compares to this .
but if the vector field is the gradient of the scalar field would n't it be path independent too ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
and then all of that times the scalar dt . this 'll be a scalar value , and then we 'll have another scalar value of dt over there . now , what is this going to be equal to if i take this reverse integral ?
another question : why we did n't use pythagoras theorem like we did in the scalar field ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that .
actually which is the area that can be found using line int of vectors ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
right ? this is just a vector field over the x-y plane . how the line integral of this vector field , of this vector field over this path , compares to the line integral the same vector field over that path . how that compares to this .
what 's the difference between positon vector valued functions and vector fields ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
so this thing , using that substitution simplifies to , and this is the whole point , that simplifies to minus integral from u is , when t is a , u is b . from b , when t is b , u is a . the integral from u is equal to b to u is equal to a of f of x of u y of u , right ?
so if direction does n't matter for scalar fields , then how come basic calculus of 1 variable gives negative areas when integrating from b -- > a versus a -- > b ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
so this thing , using that substitution simplifies to , and this is the whole point , that simplifies to minus integral from u is , when t is a , u is b . from b , when t is b , u is a . the integral from u is equal to b to u is equal to a of f of x of u y of u , right ? that is u , that is u . dot x prime of u times i...
why does x ' ( a+b-t ) not become -x ' ( u ) ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
so what we 're going to do in this video is to see what happens , how , i guess you could say , if i have some vector field f of xy equals p of xy i plus q of xy j . right ? this is just a vector field over the x-y plane .
i mean , i could write x ' as dx ( a+b-t ) /dt , right ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
so this thing , using that substitution simplifies to , and this is the whole point , that simplifies to minus integral from u is , when t is a , u is b . from b , when t is b , u is a . the integral from u is equal to b to u is equal to a of f of x of u y of u , right ?
so , when i substitute u = a+b-t in the 'numerator ' , should n't i also have to substitute dt = -du in the 'denominator ' ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
and now this is identical . this integral , this definite integral , is identical to that definite integral . we just have a different variable .
how come in a normal integral the direction matters , is n't a normal function which takes an x as input and returns y as output basically a scalar field ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
and then all of that times the scalar dt . this 'll be a scalar value , and then we 'll have another scalar value of dt over there . now , what is this going to be equal to if i take this reverse integral ?
another question : why we did n't use pythagoras theorem like we did in the scalar field ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
this is just a vector field over the x-y plane . how the line integral of this vector field , of this vector field over this path , compares to the line integral the same vector field over that path . how that compares to this .
so is the line integral of a vector field basically the work done and on a scalar field its area ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
now let 's say that we have any another position vector function . let me call it r of t. it 's a different one . it 's the green r. r of t. instead of being x of t times i , it 's going to be x of a plus b minus t times i , and instead of y of t , it 's going to be y of a plus b minus t times i .
what is the difference between the parametrized r ( t ) and c of which functions are usually integrated over ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
we just have a different variable . we 're doing dt here , we have du here , but we 're going to get the same exact number for any a or b , and given this vector f and the position vector path r of t. so just to summarize everything up , when you 're dealing with line integrals over vector fields , the direction matter...
at 1 is the first dr the same as the second dr ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this .
why do you mix vector form with unit vector form ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
and now this is identical . this integral , this definite integral , is identical to that definite integral . we just have a different variable .
in the end ( 12 ) , why is the integral in du equal to the integral in dt , considering that they are different variables ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
actually , let me take it make it even simpler . let me take this minus sign out of it . let me put a plus , and then i 'll put the minus sign out front . so the minus sign is just a scalar value , so we could put that minus sign out , you know , when you take a dot product , and if you multiply a scalar times a dot pr...
when switching the boundaries and then putting a minus sign in front of the integral , isnt that just what must be proven ?
let 's say i have a position vector function that looks like this . r of t is equal to x of t times the unit vector i plus y of t times the unit vector j . and let me actually graph this . so let 's say , r of t , i want to draw it a little bit straighter than that . so that 's my y-axis , that is my x-axis , and let '...
actually , let me take it make it even simpler . let me take this minus sign out of it . let me put a plus , and then i 'll put the minus sign out front . so the minus sign is just a scalar value , so we could put that minus sign out , you know , when you take a dot product , and if you multiply a scalar times a dot pr...
i follow the working , but i do n't understand how the final result shows them to be the same ( for the scalar field ) or opposite ( for the vector ) - surely the fact that the variables are different ( t and u ) means that regardless of the minus sign the two integrals could have completely different results ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
it keeps going to that for cosine of x . and so its tangent line is just going to be a horizontal line . so we know that this right over here is going to be 0 .
after finding the slope of a tangent line , how would you find the y intercept to make a y = mx + b equation ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
this point is going to go further and further and further to the left . so pi plus h , as h approaches 0 , is going to approach pi . if we assumed h was a negative value , then we would be approaching from here .
in limits , why do people keep saying `` as h approaches zero '' when in the end it actually will equal to zero ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
and they 're also concerning themselves with g of pi plus h. so let 's say that this right over here is the x value pi plus h. and then this right over here would be the point pi plus h , g of pi plus h -- would be this point right over here . and they 're essentially trying to find the slope between these two points ....
i understand how the formula of the tangent slope is derived but i dont understand how to find the value of slope of tangent given a function ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
this point is going to go further and further and further to the left . so pi plus h , as h approaches 0 , is going to approach pi . if we assumed h was a negative value , then we would be approaching from here .
why does the lim as h approaches 0 equal to 0 and not -1 , because when x=pi , y=-1 ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
this point is going to go further and further and further to the left . so pi plus h , as h approaches 0 , is going to approach pi . if we assumed h was a negative value , then we would be approaching from here .
would the answer be the same if h approached 0 from the left ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
let g of x equal cosine of x . so let 's actually graph that .
if , g ( x ) =cos ( x ) so , derivative =g ' ( x ) =-sin ( x ) ( which equals the slope of tangent line ) ?
let g of x equal cosine of x . so let 's actually graph that . so that would be the graph right over there . i drew it ahead of time . so this is a segment of cosine of x between x is equal to 0 and x equals pi . obviously , it keeps on going in both directions after that . and then they ask us , what is the limit as h...
this point is going to go further and further and further to the left . so pi plus h , as h approaches 0 , is going to approach pi . if we assumed h was a negative value , then we would be approaching from here .
why is sal approaching pi when h is approaching zero ?