AQA 1.2 Amount of Substance REVISION

[@Aya-zt2xg]

currently cramming 2 years worth of chemistry for the A-level exams i have in October T_T thank you for these videos

[@AlleryChemistry]

Good luck!

[@miinziiiiiii]

How did you do?

[@WhosParx]

@@miinziiiiiii by the looks of it he did so bad his parents took him out of this world just how they put him in it

[@AelHydrangea]

@@WhosParx You really aren't funny

[@UNKNOWN-jk6wv]

@@AelHydrangea Well I laughed, so yes, he is funny!!!

[@Theo.31]

Thanks 🙏🏻! I have my Amount Of Substance EOTT tomorrow, along with Kinetics. Your videos really help!!

[@K1zr786]

Thanks u helped me not go through my a level AQA book and waste time

[@cfhnjkkhhkoihgyhh9701]

Thank you soo much for these videos. Can u do A2 topics as well? Thanks again for everything

[@akshyakarthikeyan464]

you are my life saver. i have exam tomorrow . this was very helpful. thank you :)

[@AlleryChemistry]

Best of luck!

[@marianna094]

GUYS I GOT AN A* BECAUSE OF THESE VIDEOS

[@puddleduck1405]

yayyy well done

[@fryhyh]

I have a D in my mock exams in November and I have 4.5 months left until the real a levels… is it over?

[@Elsie.Berkz0]

noo just keep revising you will be amazing @@fryhyh

[@phoenixking9827]

Please let me ride you mr allery

[@SMH_]

@@fryhyh I'm on a D rn and have 2 months left. Is it over? nah pal, i'm getting that A*.

[@aleenaahmed1547]

i have a question. how to you work out equations. so for exxample lets say KOH and H20 are reacting together, how do you know what products will be formed please let me know. and thank you soo much for your help

[@vanessayeung...]

it says on the q that " Potassium reacts with Water", from that we can deduce that ions are formed in solution aka KOH formed in water. it's said in 12:56

[@aleenalailla04]

thank u - I do find this topic particularly difficult.

[@mrsmurfoo706]

when u have a test tomorrow and have done nothing until the night before

[@AlleryChemistry]

Best of luck! Certainly living on the edge. 😄

[@nolukewarm72]

30:50 Hey! Your formula for Atom Economy isn't correct, you made it 'divided by the sum of MM of all the reactants' instead of 'products' it almost got me hooked on a particular question for more than it's time Edit: I've just found out it depends on the question Thanks a lot sir

[@M10-y3b]

How come in the first question (16:28) you used the coefficient of Calcium to calculate the Mr, but in the next question (18:18) you did not take the 2 into account when calculating Mr of Potassium? Thanks

[@yhieho874]

NEVER involve cooefcient in calculating molar mass

[@MK-sh7ol]

@@yhieho874 so was he wrong?

[@jakethedog8864]

15:21 why did you times them all by two? You get the same answer without that

[@gddanielk8491]

Topic test after half term got to get a good grade thanks for this

[@aliciab385]

currently cramming for chem paper 1 on monday anyone else

[@Gottayplays]

How did exam go

[@biancabodrug4942]

Isn't the acid meant to turn red not yellow, in methyl orange?

[@jafwonta]

At 26:02 . The periodic table shows magnesium and sulfur to have different atomic masses, so you wouldn't get 0.96 for the moles for both of them. What would you do in this situation

[@AT-fz6wf]

I don't know

[@Jazzoo]

@@AT-fz6wfthank you 👍

[@parteekgarg231]

yo do get the same because the percentages are different if the percentages wr the same and u get different values it doesnt matter js divide by the smallest one and u will still get the imperical formula ( a bit late but yh)

[@phoenixraven2779]

What I get confused by is the indicators for titration - if we're trying to figure out what volume of acid/alkali neutralizes it, are we looking for the color in between to know when to close the tap of the burette? What would those colors be?

[@chamehmorad7387]

for methyl orange it would be orange, and for phenolphthalein it would be a very light pink. hope this helps!

[@nabinadhikari3889]

sir you are great...love you

[@yuniqecrypt7818]

Hey just wondering but why arent back titrations mentioned here?

[@afrinzlmao]

Also conversions from celsius to kelvin for ideal gas questions.

[@zohebmohammed8813]

@@afrinzlmao +273 right

[@kammy503]

Will u be making videos like this for A2

[@louiseee524]

for titration calculations I don't get how I'm meant to know the symbol equation for the reaction. any help appreciated!!

[@jazbean]

Well in the question they should give you the two substances that are being titrated (and their symbols). Then because its an acid-base reaction, they will react to give H2O and a salt. So for example if they give HCl being added to NaOH, you know it will give H2O and a salt, NaCl. If you can't work out the salt try looking at the numbers of atoms in the two reacting substances - e.g. there is 2H, Cl, Na and O in the reactants, so minus 2H and O for the water and it gives NaCl. It will probably be a more complicated equation in the exam so remember that there might be balancing etc to watch out for as well. Hope this helps

[@Luca_Talis]

@@jazbean Thank you, I hate how you are supposed to know the salts and products of a complicated reaction

[@louiseee524]

@@jazbean omg thank you so much !! I’ve never understood before but that makes so much sense now ! 😁

[@jazbean]

@@Luca_Talis Ikr, it's really annoying especially if you have to balance it as well

[@jazbean]

@@louiseee524 glad to know it helped!

[@srm4802]

Thank you sm for these vids :))))

[@AlleryChemistry]

No problem!!

[@ranimshaladi7174]

How did he get 47.6 g for the theoretical mass in the percentage yield section

[@vanessayeung...]

1. write out eq and balance it : 2Ca + O2 -> 2CaO 2. calculate mol of 2Ca: 32.6/40.1 = 0.812 mol 3. 2 Ca: 2 CaO = 1:1 => CaO = 0.812 mol 4. find CaO mass: mol * Mr (cuz n = m/Mr) -> 0.812 mol * (40.1 + 16.0) = 45.6g (theoretic yield)

[@goannas1]

for using equations to work out the volume of gas, I did everything right but I still got my answer as 2.84 x 10-3. I don't know if my answer is correct or if your answer is wrong.

[@AT-fz6wf]

His answer is wrong

[@georgia3349]

Is this a different video to the one from a few weeks ago?

[@AlleryChemistry]

No just correction of errors. See the annotations added.

[@dileen4671]

14:53

[@hasanhussain9136]

For empirical formula what would you do if the smallest number gave decimals for the moles of the other compounds

[@phoenixraven2779]

The decimals are usually very easy to round up or down to the nearest whole number

[@jaikijaikishan6134]

at 28:15 mins you did a mistake for the moles of hydrogen bit

[@fanglast3054]

Nah its right

[@nifemio8847]

@@fanglast3054why do you times it by two instead of divide

[@hazaragaming5525]

Thank you so much!

[@hazarabros584]

Yo u hazara?

[@hazarabros584]

I am a hazara KZbin lol

[@sophiecaris8477]

Going the whole hog

[@nafisac3782]

i love u

[@shazmeertv44]

Yeet