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in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | and i 'll tell you right now -- and this might seem very counterintuitive -- this is equal to 1 , or 1 to the zeroth power is also equal to 1 . anything that the zeroth power , any non-zero number to the zero power is going to be equal to 1 . and just to give you a little bit of intuition on why that is . | is zero to the zero power =1 ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | and if you do n't believe me , what is x squared ? x squared is equal to x times x . and if you were going to multiply that times x to the fourth , you 're multiplying it by x times itself four times . | for example in the video it was x^a x^b= x^ab ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | if i were to ask you what 3 to the second power is , or 3 squared , this is equal to 3 times itself two times . this is equal to 3 times 3 . which is equal to 9 . | how come ( 4^-3 * 3^-3 ) ^0 = ( 8^-3 ) ^0 ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | now you might have said , hey , was n't 3x times 3x times 3x . was n't that 3x to the third power ? right ? | but using that same logic , would n't that also make 0 to any power undefined ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | and i 'll tell you right now -- and this might seem very counterintuitive -- this is equal to 1 , or 1 to the zeroth power is also equal to 1 . anything that the zeroth power , any non-zero number to the zero power is going to be equal to 1 . and just to give you a little bit of intuition on why that is . | because if you try to go backwards to any previous power , you 're always going to get 0/0 , despite the fact that zero to any other power makes complete sense going in the opposite direction ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | so to go from this exponent to that exponent , maybe we should divide by 3 again . and that 's why , anything to the zeroth power , in this case , 3 to the zeroth power is 1 . see you in the next video . | what is 1 to the 0 power ? |
in this video , i want to do a bunch of examples involving exponent properties . but , before i even do that , let 's have a little bit of a review of what an exponent even is . so let 's say i had 2 to the third power . you might be tempted to say , oh is that 6 ? and i would say no , it is not 6 . this means 2 times ... | so if i say 7 to the zeroth power , what does that equal ? and i 'll tell you right now -- and this might seem very counterintuitive -- this is equal to 1 , or 1 to the zeroth power is also equal to 1 . anything that the zeroth power , any non-zero number to the zero power is going to be equal to 1 . | and what would 1 to the 1 power be ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | is multiplication a fast way of addition ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 2 times -- that 's too dark of a color . 2 times 12 . 2 times 12 is going to be two more than 2 times 11 . | do the exercises generate times tables 1 through 12 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | and if you watched the last video , what 's 2 times 0 ? well that 's 0 . so you do n't have to memorize your 0 multiplication tables because everything times 0 is 0 , or 0 times anything is 0 . so let 's see . | how come there is no negative 0 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | where are the multiplication practices pages ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 7 times 7 , 49 . 7 times 8 . seven times is going to be 7 plus this , so it 's 56 . | what is an easy way to memorize the 6,7 , and 8 times tables ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | it 's the same thing as 1 times 2 . notice , these two numbers are the same thing . what 's 2 times 2 ? | since numbers do n't stop increasing or decreasing , what exactly is the definition of infinity ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | and if you watch enough khan academy videos , and hopefully you will in the future , you 'll realize that i 'm normally not a big fan of memorization . but the one thing about multiplication is if you memorize your multiplication tables that we 'll start to do in this video , it 'll pay huge benefits the rest of your l... | how do you memorize the 11 table for multiplication ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | and if you watched the last video , what 's 2 times 0 ? well that 's 0 . so you do n't have to memorize your 0 multiplication tables because everything times 0 is 0 , or 0 times anything is 0 . so let 's see . | when you do 0 times 1 , does the 0 overpower the 1 and make the answer 0 , or vice versa ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 6 times tables , let me do it in green . 6 times 1 is 6 . that 's easy . | is there a pattern for multiples of 6 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | i 'm just going up by 4 . 32 and 36 . all right , 5 times 1 . | how to muliply 32 * 56 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | it 's the same thing as 1 times 2 . notice , these two numbers are the same thing . what 's 2 times 2 ? | how do you find multiples of large numbers quickly without calculator ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | because if you add 5 to 15 you get 20 . you get 25 , 30 , 35 , 40 , 45 . fair enough . | if dan has 4x more posters than tom and together they have a total of 30 , how many posters does tom has ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 9 times 9 is 81 . i do n't know if you can see that . 81 . | i dont know multyply and divide intigers ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | what is the purpose of multiplication ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | but every other number in its times tables is going to end with a 5 , and then every other one 's going to end with a 0 . because if you add 5 to 15 you get 20 . you get 25 , 30 , 35 , 40 , 45 . fair enough . | how did people ever get the idea of multiplacation ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | is there a good way to memorize your multiplication tables up to 20 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | why do most multiplication tables taught at young ages stop at ten or twelve ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | maybe i 'll reuse a color or two . i 'll use the blue again . 9 times 1 is 9 . | can you use scientific notation with fractions ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | is that 7 ? 1 , 2 , 3 , 4 , 5 , 6 , 7 . and that 's the same thing as 7 plus 7 , which you may or may not know is equal to 14 . | is there a multiplication practice from numbers 1 , 2 , 3 , 4 , 5 ... 12 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | let 's see . i hope i have space for this . 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 . | when everything scatters in space , why dont planets ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | well , 3 plus 3 is the same thing as 2 plus 2 plus 2 , and that 's equal to 6 . all right . now what is 2 times 4 ? | is it always better to put the smaller number ( less numbers ) right ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | it 's the same thing as 1 times 2 . notice , these two numbers are the same thing . what 's 2 times 2 ? | why do you double the numbers ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 6 times 1 is 6 . that 's easy . you add 6 to that , you get 12 . | why is multiplication so easy ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 6 times 1 is 6 . that 's easy . you add 6 to that , you get 12 . | is there an easy way to learn your nine table 's withought flash cards ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so it 's going to be two more . let 's keep going . so 2 times 7 . | how do numbers keep on going on and on and on ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . | what do the total energy points mean ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | is multiplication the opposite of division ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | is multiplication the opposite of division ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | and if you watch enough khan academy videos , and hopefully you will in the future , you 'll realize that i 'm normally not a big fan of memorization . but the one thing about multiplication is if you memorize your multiplication tables that we 'll start to do in this video , it 'll pay huge benefits the rest of your l... | how long does it typically take to memorize the multiplication table ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | but every other number in its times tables is going to end with a 5 , and then every other one 's going to end with a 0 . because if you add 5 to 15 you get 20 . you get 25 , 30 , 35 , 40 , 45 . fair enough . | why do the icons look like robots when we get 159,000 we should get to chouse a picture am i right ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | and if you watch enough khan academy videos , and hopefully you will in the future , you 'll realize that i 'm normally not a big fan of memorization . but the one thing about multiplication is if you memorize your multiplication tables that we 'll start to do in this video , it 'll pay huge benefits the rest of your l... | how do you memorize multiplication faster ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | but every other number in its times tables is going to end with a 5 , and then every other one 's going to end with a 0 . because if you add 5 to 15 you get 20 . you get 25 , 30 , 35 , 40 , 45 . fair enough . | how do you get the orange squid guy ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | i can keep going . 2 times 9 times 10 times 100 times 1,000 times 1,000,000 . but i 'm going to stop at 12 because that tends to be what people need to memorize . | what is the easiest way to memorize your 1-10 times tables without flash cards ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | i can keep going . 2 times 9 times 10 times 100 times 1,000 times 1,000,000 . but i 'm going to stop at 12 because that tends to be what people need to memorize . | what is 500 times 400 times 0 + 400 + 20 +.3= ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so it 's 6 . and that makes sense . 3 plus 3 is 6 or 2 plus 2 plus 2 is 6 . | what makes multiplication so hard ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | actually , we know that anything -- well , i want to keep changing colors , so i 'll just do it in rows like this . 5 times 1 is 5 . 5 times 2 is 10 . | for some reason on the last challenge ( multiplying 1-digit numbers ) you earn more points for getting problems wrong : total energy points earned 1 5 0 50 points for questions 12 questions answered 83 % correctly 100 points for completion bonus points earned for completing this task vs total energy points earned 1 2 5... |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so it 's going to be two more . let 's keep going . so 2 times 7 . | have flash cards to keep memory ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | notice , every time you add 9 , you go almost up by 10 , but 1 less than that . so up by 10 would be 46 , and then one less than that is 45 . but anyway , notice , the 1 's -- well , i 'll talk more about it in the future . | what school curriculums would you recommend ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | how long will it take for me to memorize my multiplication tables ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promises to you , but they 'll be better than if you did n't memorize your multiplication tables . so what are the multiplication tables ? well that 's all of the different numbers... | is there any tips on how to memorize these tables so i can recognize what the answer is when i do a multiple problem ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | but the one thing about multiplication is if you memorize your multiplication tables that we 'll start to do in this video , it 'll pay huge benefits the rest of your life . so i promise you , do it now , you 'll never forget it , and the rest of your life everything will be -- well , i do n't want to make false promis... | do you guys make third grade printables ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | actually , we know that anything -- well , i want to keep changing colors , so i 'll just do it in rows like this . 5 times 1 is 5 . 5 times 2 is 10 . | i do n't get doing the whole counting a number for the 5 's for example 4 times 5=20 but why do you have to do the four times four when you can count your fives ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 7 times 7 , 49 . 7 times 8 . seven times is going to be 7 plus this , so it 's 56 . | what 's the best way to memorize the 6 , 7 and 8 multiplication tables ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | 7 times 7 , 49 . 7 times 8 . seven times is going to be 7 plus this , so it 's 56 . | 8x7 : reverse the problem 6x7 then what comes before 7 and 8 ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | actually , i should keep going . well , i realize this video is already pretty long . i want you to memorize this right now because this is going to get you pretty far . | why is n't there long division ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | it 's the same thing as 1 times 2 . notice , these two numbers are the same thing . what 's 2 times 2 ? | what are all the numbers in pie ? |
at this point i think you know a little bit about what multiplication is . what we 're going to do in this video is to give you just a ton of more practice and start you on your memorization of the multiplication tables . and if you watch enough khan academy videos , and hopefully you will in the future , you 'll reali... | it 's going to be 22 . another interesting pattern . i have the number repeated twice -- a 2 and a 2 . | how do you memorize the addition of one # so fast to another ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | instead of 10 joules of energy , you give him $ 10 , and ask you , `` how much total energy is there `` between you and your friend ? '' well , there 's still the total amount . you lost $ 10 . | however , right before the object hits the ground , should n't there be a small amount of pe since the object still has height ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | so recapping , lol diagrams are a great way to visualize what we 're talking about when we say conservation of energy . and since we define our system , they 're a nice way to visualize what we mean when we say that the total initial energy of our system , plus any external work done on our system has to equal the tota... | what is the period of the oscillating system ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | now there 's external work done , but instead of the external work giving our system energy , the external work is taking energy away . this friction is taking energy and turning it into thermal energy . that 's what this extra spot is here , for thermal energy . | however , if i remember correctly , in previous articles , it said that some of the energy would be converted into thermal energy , since right at the moment the block hits the earth , some friction happened ... is it that the thermal energy is so small it is able to be neglected ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | let me get rid of this . let 's instead consider this example , where a mass starts compressed against the spring from rest . that 'll be our initial point . | initially the ball 's position is 0.00 m.if the spring is compressed by =-0.20 m , what will the position the ball be when its released ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | we can write this in an equation again by saying that the total energy we start with , the spring energy , which would be 1/2 k x squared , plus any external work done , but the external work done was zero , since everything is internal , has to equal the final energy . and the final energy here is the kinetic energy ,... | when h=0 then how will be there gravitational potential energy ? |
i wan na talk to you about lol diagrams . that 's right , i said lol diagrams . these are a great ways to visualize conservation of energy , and even better , they force you to think about what 's part of your energy system and what is n't part of your energy system . and if you do n't know what an energy system is , ... | but since the surfaces are now not part of our system , we would n't show that over here . we would just include that as part of the external work done , so there would be some negative amount of work done . maybe the surfaces did negative one unit of external work . | the force due to gravity acts for a significant amount of time , so would there be an impulse also ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | so that 's going to be the nucleophile , and it 's going to attack our partially positive carbon . an sn2 type mechanism . so as the chloride attacks , this stuff on the right is going to leave . | 8 why would it be an sn2 if that is a tertiary carbon and sn2 rxn only happens in primary and secondary carbons ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and so we 've done it . we 've substituted our chlorine atom for the oh and formed an alkyl halide . so this is just a better way of forming an alkyl chloride from an alcohol . so if we look at an example , we 'll just take something like ethanol here . | is there any way to make an alkyl halide from a tertiary alcohol ( by an sn1 reaction ) ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | it 's ok for sulfur to violate the octet rule , since it is in the third period now . so a lone pair of electrons on oxygen is going to form a bond with our sulfur atom , which would therefore kick these electrons in here off onto the top oxygen . so if we go ahead and draw what we get from that first step of our mecha... | why did n't the bond electrons move to the chlorine atom instead of oxygen atom ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and so when we show the result of that , we would now have our oxygen bonded to a phosphorus . the oxygen is still bonded to a hydrogen . there 's still a lone pair of electrons left behind on this oxygen , which gives this oxygen a plus 1 formal charge . and the phosphorus is now bonded to only two bromines . | why does the oxygen has a positive charge with it is bonded to socl2 or pbr3 ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | one lone pair of electrons formed that new bond , so one pair of electrons is left behind . which would give this oxygen a plus 1 formal charge . connected to the sulfur , this top oxygen here had two lone pairs of electrons . | i still do not understand why o would lose an electron to give +1 charge ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | so if we look at an example , we 'll just take something like ethanol here . and if we react ethanol with thionyl chloride , socl2 , and we had some pyridine as our base . we 're going to replace the oh with our chlorine like that . | is there any special reason for using pyridine as a base in many alcohols ' rxns ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | so it once it wants negatively charged electrons , which it could get from the bromide anion . so nucleophilic attack , and then that would kick these electrons in here off on to your oxygen . and we can go ahead and show our products . | why doed the oxygen attack the p ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | so i go ahead and have my alcohol . and i react that with phosphorus tribromide , pbr3 . the oh group is going to leave and i 'm going to put a bromine in its place . | also i have heard usage of pbr5 instead of pbr3 for bromination , does it imply the same meaning ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and of course we 're going to replace the oh with a bromine . and so that 's one way to prepare alkyl halides from alcohols . | can you just suggest a way to prepare an alkyl iodide from alcohols ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | when we look at this mechanism here , let 's go ahead and show that lone pair of electrons better , like that . we have phosphorus tribromide . so i 'm going to go to draw the dot structure . | why does my professor not complete phosphorus ' octet ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . | and why is ether necessary ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | one lone pair of electrons formed that new bond , so one pair of electrons is left behind . which would give this oxygen a plus 1 formal charge . connected to the sulfur , this top oxygen here had two lone pairs of electrons . | in the last step in the second reaction , why did the bromide anion attack the carbon atom not the the oxygen atom that has a +1 formal charge ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and we do n't have to worry about stereochemistry , since we do n't have any chirality centers in our product . let 's look at a way to form alkyl bromide . so we just formed an alkyl chloride . | sir can we use pbr5 to react with alchols to form alkyl bromides ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | so i go ahead and have my alcohol . and i react that with phosphorus tribromide , pbr3 . the oh group is going to leave and i 'm going to put a bromine in its place . | pbr3 will give 3 molecule of alkylhalid with phosphors acid i think ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | one lone pair of electrons formed that new bond , so one pair of electrons is left behind . which would give this oxygen a plus 1 formal charge . connected to the sulfur , this top oxygen here had two lone pairs of electrons . | if you had to make a cyclic haloalkane , how would you know whether to pick hcl or socl2 and why ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and then still there 's a lone pair of electrons on our sulfur like that . so at this part of the mechanism , the pyridine comes along . so if we go ahead and draw the dot structure for pyridine . it 's a base , and so it looks like a benzene ring , except we have a nitrogen here instead . | does pyridine prevents reversibility of the reaction ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and then still there 's a lone pair of electrons on our sulfur like that . so at this part of the mechanism , the pyridine comes along . so if we go ahead and draw the dot structure for pyridine . it 's a base , and so it looks like a benzene ring , except we have a nitrogen here instead . | does pyridine prevents reversibility of the reaction ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and we do n't have to worry about stereochemistry , since we do n't have any chirality centers in our product . let 's look at a way to form alkyl bromide . so we just formed an alkyl chloride . let 's look at the general reaction for forming an alkyl bromide here . | why does the formation of an alkyl chloride ( 0 ) require a base , while the formation of an alkyl bromide ( 0 ) does n't ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | and so when we show the result of that , we would now have our oxygen bonded to a phosphorus . the oxygen is still bonded to a hydrogen . there 's still a lone pair of electrons left behind on this oxygen , which gives this oxygen a plus 1 formal charge . and the phosphorus is now bonded to only two bromines . | sorry for the typo , let me retype the question again : why does the oxygen has a positive charge when it is bonded to sulphur in socl2 or bromine in pbr3 ? |
in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . we 're going to substitute a chlorine atom for the oh group . and this mechanism occurs via an sn2 type m... | in this video we 're going to see how to prepare alkyl halides from alcohols . and so if we start with this alcohol over here on the left , and we add socl2 , which is called thionyl chloride , and pyridine to it . | during 0xidati0n b0th kmn04 & k2cr207+h2s04 can be used at the same time ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | once again this acid-base equilibrium favors the formation of our product , so this helps to drive the reaction forward . we drive the reaction forward . finally let 's think about how we would get from a carboxylate anion to our carboxylic acid product . | around why does the nh2- takes the h from r-cooh and not the h+ from the solution ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | let 's get some more room here . we have another acid base reaction . we 're going to protonate the amine because that 's going to give us a better leaving group . | in the base-catalyzed reaction , it would not be favorable for the amino group to be protonated because + charge is not favorable in basic solutions , right ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | the lone pair of electrons right here on the oxygen is going to pick up a proton from hydronium , forming this bond right here and giving the oxygen a plus one formal charge . to think about a resonance structure for this , it 's going to withdraw some electron density from our carbonyl carbon here , making that carbon... | why does resonance destabilize the carbon then ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | we have nh2 but let 's think about our electrons . we already have a lone pair of electrons on the nitrogen , and we got another lone pair . let me show where that came from . | under base catalysed hydrolysis , why does lone pair of oxygen moves to form carbonyl and nh2 leaves ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | we have an r group , we would have our carbonyl has been reformed , we would have our oxygen and our hydrogen . we formed our carboxylic acid . let me put these electrons here in blue so we can see which ones they are , like that . | since the carboxylic acid is the intended final product of this mechanism , why not stop right ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | if we have nh2 minus and we 're adding a proton to that then we would form nh3 . we form ammonia . let me go ahead and draw in ammonia here . | so does the amide anion ever form in this case ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | let 's say these electrons right here on hydroxide are the ones that form this bond between the carbon and the oxygen . now we can reform our carbonyl . we 're going to reform our carbonyl here . | what compels the unpaired electrons on o to reform the carbonyl group ? |
: we 've already see that amides are generally unreactive due to resonance stabilization , however you can get them to hydrolyze if you use harsh reaction conditions . if you use strong acid or a strong base and you heat things up for several hours , you can hydrolyze amides . if we take a look at this amide right her... | we have nh2 but let 's think about our electrons . we already have a lone pair of electrons on the nitrogen , and we got another lone pair . let me show where that came from . | under base catalysed hydrolysis , why does lone pair of oxygen moves to form carbonyl and nh2 leaves ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | and we 'll talk in the future about why this is , and the reason why this is defined this way , is it has all sorts of neat and elegant properties when you start manipulating the actual exponents . but what is the square root of 4 , especially the principal root , mean ? well that means , well , what is a number that i... | what is the principal root of a number ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | and the cube root is just saying , well what number , if i had three of that number , and i multiply them , that i 'm going to get 8 . so something , times something , times something , is 8 . well , we already know that 8 is equal to 2 to the third power . | do you take the square root and then multiply , or do something else ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | so this says hey , give me the number that if i were to multiply that number , or i were to repeatedly multiply that number five times , what is that , i would get 32 . well , 32 is the same thing as 2 times 2 times 2 times 2 times 2 . so 2 is that number , that if i were to multiply it five times , then i 'm going to ... | what do you do when you have for example 2/3 to the power of 2 ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | and we 'll talk in the future about why this is , and the reason why this is defined this way , is it has all sorts of neat and elegant properties when you start manipulating the actual exponents . but what is the square root of 4 , especially the principal root , mean ? well that means , well , what is a number that i... | the only options that come up are cube root symbol and square root ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | well , we already know that 8 is equal to 2 to the third power . so the cube root of 8 , or 8 to the 1/3 , is just going to be equal to 2 . this says hey , give me the number that if i say that number , times that number , times that number , i 'm going to get 8 . | okay what are the 3 cube roots of 8 ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | but either way , this is going to result in 4 times 4 is 16 , times 4 is 64 . we also know a little bit about negative exponents . so for example , if i were take 4 to the negative 3 power , we know this negative tells us to take the reciprocal 1/4 to the third . | is there anywhere i could find how to divide negative exponents ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | i think you 're starting to see a little bit of a pattern here , a little bit of symmetry here . and we can extend this idea to arbitrary rational exponents . so what happens if i were to raise -- let 's say i had , let me think of a good number here -- so let 's say i have 32 . | is there any way the value of a rational exponent can be calculated ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | this says hey , give me the number that if i say that number , times that number , times that number , i 'm going to get 8 . well , that number is 2 because 2 to the third power is 8 . do a few more examples of that . | at no part of the video did sal explain what to do if a number is raised to , for example , the 2/5th power ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | do a few more examples of that . what is 64 to the 1/3 power ? well , we already know that 4 times 4 times 4 is 64 . | what if the fraction has an integer larger than 1 for its numerator ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | but either way , this is going to result in 4 times 4 is 16 , times 4 is 64 . we also know a little bit about negative exponents . so for example , if i were take 4 to the negative 3 power , we know this negative tells us to take the reciprocal 1/4 to the third . | hi how you doing i am wondering how do you solve if the base is negative or if the exponent is negative ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | and we 'll talk in the future about why this is , and the reason why this is defined this way , is it has all sorts of neat and elegant properties when you start manipulating the actual exponents . but what is the square root of 4 , especially the principal root , mean ? well that means , well , what is a number that i... | the first question on the practice section is : b^1/4 - so , this it is the 4th root of b , right ? |
we already know a good bit about exponents . for example , we know if we took the number 4 and raised it to the third power , this is equivalent to taking three fours and multiplying them . or you can also view it as starting with a 1 , and then multiplying the 1 by 4 , or multiplying that by 4 , three times . but eith... | so based on what i just told you , what do you think 9 to the 1/2 power is going to be ? well , that 's just the square root of 9 . the principal root of 9 , that 's just going to be equal to 3 . | how do i enter my answer when the only options are square roots and cubed roots ? |
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