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My 10th grade chemistry book states that:
>"Metals react with water and produce a metal oxide and hydrogen gas. Metal oxides that are soluble in water dissolve in it to further form metal hydroxide.
Metals like potassium and SODIUM react violently with cold water. In case of sodium and potassium, the reaction is so v... |
My 10th grade chemistry book states that:<br>
"Metals react with water and produce a metal oxide and hydrogen gas. Metal oxides that are soluble in water dissolve in it to further form metal hydroxide.
Metals like potassium and SODIUM react violently with cold water. In case of sodium and potassium, the reaction is s... |
My 10th grade chemistry book states that:
>"Metals react with water and produce a metal oxide and hydrogen gas. Metal oxides that are soluble in water dissolve in it to further form metal hydroxide. Metals like potassium and SODIUM react violently with cold water. In case of sodium and potassium, the reaction is so ... |
I am confused about the application of Le Chatelier's principle to reaction systems. Consider the reaction: $$\ce{H2O2(g) <=> 2OH{.}(g)}\quad\text{(i)}$$ to be at at equilibrium. As the pressure is increased, the reaction moves towards forming $\ce{H2O2}$ as this direction reduces the amount of substance in the system.... |
I am considering building a stove out of stainless steel. I want to us stainless steel because the stove will have a double outer jacket to pass water through and heat it.
Will a wood fire sitting directly on stainless steel corrode it? Would a higher grade of stainless steel, say 316 instead of 304, prevent this?
... |
My 10th grade chemistry book states that:
>"Metals react with water and produce a metal oxide and hydrogen gas. Metal oxides that are soluble in water dissolve in it to further form metal hydroxide. Metals like potassium and **sodium** react violently with cold water. In case of sodium and potassium, the reaction is... |
My 10th grade chemistry book states that:
>"Metals react with water and produce a metal oxide and hydrogen gas. Metal oxides that are soluble in water dissolve in it to further form metal hydroxide. Metals like potassium and **sodium** react violently with cold water. In case of sodium and potassium, the reaction is... |
I have been taught that the MO diagram is different for molecules with 14 or less electrons than the one used for molecules with 15 or more electrons. For $N_2$ the orbitals are: $(\sigma 1s)( \sigma^*1s) (\sigma 2s)( \sigma^*2s)(\pi 2p_z)=(\pi 2p_y)(\sigma 2p_x)(\pi^* 2p_z)=(\pi^* 2p_y)(\sigma^* 2p_x)$ because it has ... |
I have been taught that the MO diagram is different for molecules with 14 or less electrons than the one used for molecules with 15 or more electrons.
For $\ce{N2}$ the orbitals are:
$(\sigma 1s)( \sigma^*1s) (\sigma 2s)( \sigma^*2s)(\pi 2p_z)=(\pi 2p_y)(\sigma 2p_x)(\pi^* 2p_z)=(\pi^* 2p_y)(\sigma^* 2p_x)$
... |
Fluorine is the most electronegative halogen and therefore, there is larger difference in electronegativity between the atoms of $\ce{HF}$ than any other Hydrogen Halide, which means the positive charge on Hydrogen atom is the greatest in this compound and hence a comparatively small negative charge is needed to attrac... |
Why is HF the least acidic hydrogen halide? |
Fluorine is the most electronegative halogen and therefore, there is larger difference in electronegativity between the atoms of $\ce{HF}$ than any other hydrogen halide, which means the positive charge on hydrogen atom is the greatest in this compound and hence a comparatively small negative charge is needed to attrac... |
I know that the exact (OK most of the times not the exact) energy of an electron can be calculated by solving Strodinger's differential equetion. However, can we explain an electron's energy of a specific orbital using the Penetration and Shielding effect? |
I know that the exact (OK most of the times not the exact) energy of an electron can be calculated by solving Schrodinger's differential equation, but can we explain an electron's energy of a specific orbital using the Penetration and Shielding effect? |
The Zeff increases from left to right and from top to bottom. Can you explain why it increases from top to bottom?
Also can we explain the periodic trend of electronegativity using the shielding effect? |
> Can we explain an electron's energy of a specific orbital using the
> Penetration and Shielding effect?
Yes, *to some extent* it is possible. Look no further than [Slater's rules][1] which specifies the values of the effective nuclear charge $Z^*$, and the effective principal quantum number $n^*$ that can be used... |
> Can we explain an electron's energy of a specific orbital using the
> Penetration and Shielding effect?
Yes, *to some extent* it is possible. Look no further than [Slater's rules][1] which specifies the values of the effective nuclear charge $Z^*$, and the effective principal quantum number $n^*$ that can be used... |
The $\mathrm{Z_{eff}}$ increases from left to right and from top to bottom. Can you explain why it increases from top to bottom?
Also can we explain the periodic trend of electronegativity using the shielding effect? |
I know that *[iron(II) sulfate][1] (ferrous sulfate)* is a salt that in solution separates to its ions $\mathrm{Fe^{2+},SO_4^{2-}}$ (and shortly after [decomposes to ferric sulfate][2]).
But what happens to to [iron(III) sulfate][3] (ferric sulfate) in solution? Does it maintain its $\mathrm{Fe_2(SO_4)_3}$ compound ... |
What happens to iron(III) sulfate (ferric sulfate) in aqueous solution? |
First of all as @chipbuster says HF in diluted solutions in water is nearly completely dissociated and therefore shouldn't be called weak. [Wikipedia][1] describes this nicely and cites [several][2] [sources][3] for this claim.
It was rather difficult to prove (spectroscopic methods were used), because hydronium ion... |
I know that density decreases across period 4 because the last two elements are liquids and gases which means that their densities are less but why are the densities increasing and then decreasing within the transition metals themselves? |
Why does density decrease across the period 4 and 5 transition metals? |
As in weight per volume? I mean.. you always see them specified by weight but they have to have a volume, right?
I suppose different fat(for example) molecules would have different densities but then how do they universally have the same energy density? Are they converted to like a standardized type of fat? Thats th... |
What is the density of carbohydrates/protein/fat? |
> I have been taught that the MO diagram is different for molecules with
> 14 or less electrons than the one used for molecules with 15 or more
> electrons.
This is (partly) wrong because the change in the order of $\mathrm{\sigma_{2p_{z}}}$ and $\mathrm{\pi_{2p_{xy}}}$ MOs to the left of $\ce{N2}$ is not directly... |
The $\mathrm{Z_{eff}}$ increases from left to right and from top to bottom. Can you explain why it increases from top to bottom?
Also can we explain the periodic trend of electronegativity using the shielding effect?
**EDIT:**
The calculation of $Z_{eff}$ for Li would be 1 (3 protons - 2 core electrons). For Na... |
The effective nuclear charge $Z_\mathrm{eff}$ increases from left to right and from top to bottom. Can you explain why it increases from top to bottom?
Also can we explain the periodic trend of electronegativity using the shielding effect?
**EDIT:**
The calculation of $Z_\mathrm{eff}$ for Li would be 1 (3 proto... |
I came across this in phenols:
> The hydroxyl group, in phenol is directly attached to
the sp2
hybridised carbon of benzene ring which acts as an
electron withdrawing group. Due to the higher electronegativity of sp2
hybridised carbon
of phenol to which –OH is attached, electron density decreases
on oxygen. ... |
What is the reason for the acidic character in phenols? |
I came across this in phenols:
> The hydroxyl group, in phenol is directly attached to
the sp2
hybridised carbon of benzene ring which acts as an
electron withdrawing group. Due to the higher electronegativity of sp2
hybridised carbon
of phenol to which –OH is attached, electron density decreases
on oxygen. ... |
I assume the "energy density" you are referring to are the widely known statistics that:
- fat contains 9 "calories" per gram (actually kilocalories)
- protein and carbohydrates both contain 4 "calories" per gram
How can all fats contain "9" kcal per gram but have different mass densities? Here are a couple o... |
I am working on a mathematical model for the dissolution of coffee in water. I need to know some precise details about the effects of dissolution on the density of the mixture of the substances. Ie. the density of the solution. The system is isothermal and the pressure is constant (so that temperature and pressure do c... |
Is the density of the solution significantly different from the density of the solvent? |
> I have been taught that the MO diagram is different for molecules with
> 14 or less electrons than the one used for molecules with 15 or more
> electrons.
This is (partly) wrong because the change in the order of $\mathrm{\sigma_{2p_{z}}}$ and $\mathrm{\pi_{2p_{xy}}}$ MOs to the left of $\ce{N2}$ is not directly... |
I am working on a mathematical model for the dissolution of coffee in water. I need to know some precise details about the effects of dissolution on the density of the mixture of the substances (that is, the density of the solution). The system is isothermal and the pressure is constant. I just want to focus on mass, v... |
Like when an e- withdrawing group (sp2 carbon) is attached to oxygen of the OH bond, it attracts the electrons. So will the polarity of the OH bond increase or decrease? |
In an O-H bond, will polarity increase/decrease if some of the electron density on the oxygen atom is reduced? |
> I have been taught that the MO diagram is different for molecules with
> 14 or less electrons than the one used for molecules with 15 or more
> electrons.
This is (partly) wrong because the change in the order of $\mathrm{\sigma_{2p_{z}}}$ and $\mathrm{\pi_{2p_{xy}}}$ MOs to the left of $\ce{N2}$ is not directly... |
[Iron(II) sulfate][1] (ferrous sulfate) is a salt that, in an aqueous solution, dissolves and yields $\ce{Fe^{2+}}(aq)$ and $\ce{SO4^{2-}}(aq)$. It then [decomposes to ferric sulfate][2] shortly thereafter.
But what happens to the [iron(III) sulfate][3] (ferric sulfate) in solution? Is the $\ce{Fe_2(SO_4)_3}$ compou... |
In chemistry one can recognize that the four states of matter are: solid, liquid, gas and plasma. The first is rigid, and has a definite shape and volume. The second doesn't have a shape, and assumes the shape of its container, however it has a fixed volume. The third doesn't have neither a shape nor a fixed volume an... |
Following a book of science experiments for children with my daughter, we did the following:
- put some water in a shallow dish;
- put some ground pepper floating on the water surface;
- touch the water surface with the tip of a small stick previously dipped in liquid soap;
- then the floating pepper escapes ... |
What makes dimerization possible in $\ce{AlCl3}$? Are there 3c-2e bonds in $\ce{AlCl3}$ as in $\ce{BH3}$? |
Why is $\ce{BCl3}$ a monomer whereas $\ce{AlCl3}$ exists as a dimer? |
Why is BCl3 a monomer whereas AlCl3 exists as a dimer? |
[Iron(II) sulfate][1] (ferrous sulfate) is a salt that, in an aqueous solution, dissolves and yields $\ce{Fe^{2+}(aq)}$ and $\ce{SO4^{2-}(aq)}$. It then [decomposes to ferric sulfate][2] shortly thereafter.
But what happens to the [iron(III) sulfate][3] (ferric sulfate) in solution? Is the $\ce{Fe_2(SO_4)_3}$ compou... |
In chemistry one can recognize that the four states of matter are solid, liquid, gas and plasma. The first is rigid, and has a definite shape and volume. The second doesn't have a shape, and assumes the shape of its container, but it has a fixed volume. The third doesn't have either a shape or a fixed volume and assume... |
First of all as @chipbuster says HF in diluted solutions in water is nearly completely dissociated and therefore shouldn't be called weak. [Wikipedia][1] describes this nicely and cites [several][2] [sources][3] for this claim.
It was rather difficult to prove (spectroscopic methods were used), because hydronium ion... |
First of all as @chipbuster says HF in diluted solutions in water is nearly completely dissociated and therefore shouldn't be called weak. [Wikipedia][1] describes this nicely and cites [several][2] [sources][3] for this claim.
It was rather difficult to prove (spectroscopic methods were used), because hydronium ion... |
According to the lowest locant rule, 2,3-dimethyl cyclopentene should be the correct IUPAC name as the sum of the locants of the substituents(2+3=5) of 2,3-dimethyl cyclopentene is lower than the sum of the locants of the substituents(1+5=6) of 1,5-dimethyl cyclopentene.
But my book says that the correct name of the ... |
Which is the correct name: 2,3-dimethyl cyclopentene or 1,5-dimethyl cyclopentene? |
I'm not an expert in chemistry, so please correct me if something in the question is fundamentally flawed. :) Anyways, there are a lot of diy cleaner solutions out there, using a combination of vinegar, alcohol (in a "cheap vodka" concentration), dish soap, baking soda and essential oils. I like these recipes for two r... |
What alcohol concentration makes bathroom cleaner 'disinfecting'? |
There are many do-it-yourself cleaner solutions out there, using a combination of vinegar, alcohol (in a "cheap vodka" concentration), dish soap, baking soda and essential oils. I like these recipes for two reasons, first for cost and second for health (sometimes my toddler helps me clean his bathtub, and I wouldn't wa... |
What alcohol concentration makes bathroom cleaner "disinfecting"? |
I am trying to figure how would I go about finding a dopant element that would fit in a copper lattice? I already have the data for the atomic dimensions and structure (available below), however how would I find a dopant element that would make it a P-Type material? (Relatively new to chemistry, so bear with me if I as... |
It is probably easiest for me to explain the question in an example. Consider the following chemical formula.
#MgF2 (s) ---> Mg2+ (aq) + 2F - (aq)#
Plugging this into the solubility product constant, $K_{sp}=[M^{y+}]^{x}[A^{x-}]^{y}$, we get $K_{sp}=[Mg^{2+}]\times[F^{-}]^{2}$.
The solubility product constant fo... |
Why are the reactants in the solubility product constant multiplied by their coefficients and raised to the power of their coefficients? |
This is going to be a longshot, and I might be wrong in any and all of my assumptions, be warned ( ... and please correct me). I might also be trivially right, I have no idea.
At equilibrium, each degree of freedom has the kinetic energy:
$ E = \frac{1}{2}k_bT $
So, I have water at, say, 300K. Water has three ... |
Can we know the amplitude of vibration of O-H bonds in water? |
It is probably easiest for me to explain the question in an example. Consider the following chemical reaction:
$\ce{MgF2(s) -> Mg^{2+} (aq) + 2F- (aq)}$
Plugging this into the formula for the solubility product constant, $K_{sp}=[M^{y+}]^{x}[A^{x-}]^{y}$, we get:
$K_{sp}=[\ce{Mg^{2+}}][\ce{F-}]^{2}$.
The s... |
is the absolute temperature concept is 100% right? |
Maybe I'm wrong about it but I wanted to know whether the concept of absolute temperature is real or not.
As every element behaves differently at a particular temperatures how could we assign a common temperature to all these elements where they possess zero point energy? If they will do so then what will happen if... |
Is the absolute temperature concept 100% viable? |
Why does equilibrium exist? |
Maybe I'm wrong about it but I wanted to know whether the concept of absolute temperature is real or not.
As every element behaves differently at a particular temperatures how could we assign a common temperature to all these elements where they possess zero point energy? If they will do so then what will happen if... |
Are names of substituents like isopropyl and sec-butyl accepted by IUPAC?
Or do we need to name them according to standard IUPAC conventions?
(Ex- 1-methylethyl for isopropyl)
My book uses common names for substituents at a lot of places but I am doubtful about this. |
Are common names of substituents accepted by IUPAC? |
This is a question that appeared in Atkin's Physical Chemistry Book in the Chapter 3 exercise questions. It is question 3.3(a):
**Question**
Calculate $\Delta S$ when the state of 3mol of perfect gas atoms, for which $C_{p,m}$ = $\frac{5}{2}R$, is changed from 298K and 1atm to 398K and 5atm. How do you rationaliz... |
This is a question that appeared in Atkin's Physical Chemistry Book in the Chapter 3 exercise questions. It is question 3.3(a):
**Question**
Calculate $\Delta S$ when the state of $\mathrm{3~mol}$ of perfect gas atoms, for which $C_{p,m}$ = $\frac{5}{2}R$, is changed from $\mathrm{298~K}$ and $\mathrm{1~atm}$ to ... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/dmHqO.png
This is a question I was trying to solve, from an IB Chemistry past paper. My question is how do these reactions help determine the percentage of copper in brass?
Any help will be greatly appreciated, thanks in advance. |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/dmHqO.png
This is a question I was trying to solve, from an IB Chemistry past paper.
I looked it up and found out that brass is an alloy of copper and zinc - however, I don't see zinc in any of the equations, and therefore any brass bein... |
I'm not a chemist and don't remember much chemistry from school, so please forgive a naive question (I've read the Wikipedia article on sodium silicate though).
I'm researching this topic to make a positive photo resist developer for making PCBs.
1. Will dissolving Na2SiO3 (the ahydrous form) in water produce... |
I'm not a chemist and don't remember much chemistry from school, so please forgive a naive question (I've read the Wikipedia article on sodium silicate though).
I'm researching this topic to make a positive photo resist developer for making PCBs.
1. Will dissolving Na2SiO3 (the ahydrous form) in water produce... |
I'm not a chemist and don't remember much chemistry from school, so please forgive a naive question (I've read the Wikipedia article on sodium silicate though).
I'm researching this topic to make a positive photo resist developer for making PCBs.
1. Will dissolving $\ce{Na_{2}SiO_{3}}$ (the ahydrous form) in ... |
This is going to be a longshot, and I might be wrong in any and all of my assumptions, be warned ( ... and please correct me). I might also be trivially right, I have no idea.
At equilibrium, each degree of freedom has the kinetic energy:
$ E = \frac{1}{2}k_bT $
So, I have water at, say, 300K. Water has three ... |
Finally, I have a day off to read that question and response. Half-way readind it I was already a bit suspicious mostly because of the half-jolly and half-formal style OP used. :) Don't get me wrong, in principle I have nothing against such style. But the thing is that usually when such style is used some nonsense is e... |
This is going to be a longshot, and I might be wrong in any and all of my assumptions, be warned (... and please correct me). I might also be trivially right, I have no idea.
At equilibrium, each degree of freedom has the kinetic energy:
$ E = \frac{1}{2}k_\mathrm bT $
So, I have water at, say, $300\ \mathrm K... |
[![enter image description here][1]][1]
There is cyclopentyl attached to one terminal carbon atom and cyclohexyl attached to the other terminal carbon atom and there are three carbon atoms linking them. Since the cyclohexyl ring has the greatest number of carbon atoms, it should be the parent chain. So the name shou... |
What should be the parent chain in this hydrocarbon? |
I'm not a chemist and don't remember much chemistry from school, so please forgive a naive question (I've read the Wikipedia article on sodium silicate though).
I'm researching this topic to make a positive photo resist developer for making PCBs.
1. Will dissolving $\ce{Na_{2}SiO_{3}}$ (the ahydrous form) in ... |
I wear corrective eyeglasses, and because of this, I frequently experience problems with fogging when I wear safety goggles. How can I prevent or reduce fogging?
Details:
---
The safety goggles I use are the standard-issue goggles supplied by the campus store, but I can use other goggles rated at least Z87+D3 ("+"... |
How to stop goggles from fogging? |
what kind of storage solution is required for an electrode (glass)? Is 3M KCl OK for this purpose? If so, what is roughly the pH of that solution (mine is around 5)? Can filling solutions be used as storage solutions? Thanks. |
The mechanism of the olefine metathesis using Grubbs' catalyst consists of [2+2] cycloadditions and reverse cycloadditions. The Wittig reaction, too. How are they in accordance with the Woodward-Hoffmann rules? I think that there are two (4q+2)s components and that's not an odd number. Also why does hydroboration work? |
The mechanism of the olefine metathesis using Grubbs' catalyst consists of [2+2] cycloadditions and reverse cycloadditions. The Wittig reaction, too. How are they in accordance with the Woodward-Hoffmann rules? I think that there are two (4q+2)s components and that's not an odd number. Also why does hydroboration work ... |
Be careful with desiccant: silica may create tiny dust particles that could scratch the cornea, and hygroscopic salts may liquefy, possibly irritating.
A traditional anti-fog treatment is to rub the interior of the lens with bar soap (or a drop of mild detergent) and polish it. The soap decreases the surface tension... |
I'm not a chemist and don't remember much chemistry from school, so please forgive a naive question (I've read the Wikipedia article on sodium silicate though).
I'm researching this topic to make a positive photo resist developer for making PCBs.
1. Will dissolving $\ce{Na2SiO3}$ (the anhydrous form) in water... |
According to Ahn.N.T "Frontier Orbitals" hydroboration isn't a pericyclic reaction because boron uses two AOs and not one. The same applies for cheletropic reactions, which aren't pericyclic either. But the IUPAC goldbook says different: http://goldbook.iupac.org/P04491.html - that cheletropic reactions are pericyclic.... |
Is hydroboration a pericyclic reaction? |
Why does lactose-free milk last so much longer than regular milk? |
What kind of storage solution is required for a glass electrode?
Is 3 M $\ce{KCl}$ sufficient for this purpose? If so, what is the approximate pH of that solution (the solution I use presently has a pH $\approx$ 5)?
Can filling solutions be used as storage solutions for glass electrodes? |
Finally, I have a day off to read that question and response. Half-way reading it I was already a bit suspicious mostly because of the half-jolly and half-formal style OP used. :) Don't get me wrong, in principle I have nothing against such style. But the thing is that usually when such style is used some nonsense is e... |
The mechanism of the olefine metathesis using Grubbs' catalyst consists of [2+2] cycloadditions and reverse cycloadditions. The Wittig reaction, too. How are they in accordance with the Woodward-Hoffmann rules? I think that there are two (4q+2)s components and that's not an odd number. Also why does hydroboration work? |
So, at the anode of a fuel cell hydrogen is split into a positively charged proton and an electron. Then, there is the membrane which can let only protons through to the cathode, whereas electrons need to follow external circuit (effectively powering it).
Question: why in hell do we need any other reaction on the ca... |
So, at the anode of a fuel cell hydrogen is split into a positively charged proton and an electron. Then, there is the membrane which can let only protons through to the cathode, whereas electrons need to follow external circuit (effectively powering it).
Question: why do we need any other reaction on the cathode? I... |
Why are two electrodes required in a fuel cell? |
Why is the cathode reaction required in a fuel cell? |
> My question is: is it possible to know the amplitude of
> oscillation/stiffness constant of a O−H bond?
**Yes.**
Your approach is along the right lines **but** -
The Hooke's Law formula you used
$$\mathrm{E = \frac{1}{2}kA^2}$$
is for the stretching of a spring. Hooke's law changes if the spring has... |
This is going to be a long shot, and I might be wrong in any and all of my assumptions, be warned (... and please correct me). I might also be trivially right, I have no idea.
At equilibrium, each degree of freedom has the kinetic energy:
$ E = \frac{1}{2}k_\mathrm bT $
So, I have water at, say, $300\ \mathrm ... |
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