Thank you chemistry tutor! My cie a level exam results just got out and I scored A in chemistry. It is a huge achievement for me, given I scored D on my mock exams. Thank you for your videos which have been very helpful during preparation!
I know this is off topic, but are you expected to know the full balanced autocatalysis equations, or are you expected to work out how to balance it. Balancing it is extremely tricky with the CO2 involu
Good question. I'd recommend remembering the beginnings of the half Equations So MnO4^1- --> Mn2+ C2O4^2- --> CO2 And then you balance them and add then together Less to remember and the MnO4^1- Equation is relevant elsewhere too
Hi sir thanks for the video. I have an unrelated question if you’d be so kind to help. When do you you know when to use delta s = rlnk compared to delta s = rtlnk One equation has the temperature in it, in some questions you need to use the one including temperature but I’m not sure when. Do your exclude temperature when the temperature is room temp I.e standard conditions. Thanks.
I'm a bit surprised youre seeing both! The more common equation you will see written is delta G = -RTln(K). Using the equation delta G= delta H - T*delta S we can say that at equilibrium delta S = (delta H)/T + Rln(K). If delta H = 0 this gives delta S = R*ln(K). It is not really of interest to relate this equation with delta S = nR*ln(V2/V1) since these equations account for the changes in entropy of different processes.
@@chemistrytutor Thanks for the explanation, so when would we use the one without the temperature. I had seen a question but it didn’t say that delta h was zero, but they still excluded the temperature from the equation in the calculation. Temperature was 298K.
@@st56767 did they give you some other clue such as its at equilibrium maybe? Is it edexcel that you do? They are often quite tricky about only giving subtle clues about how to approach their questions
Thank you chemistry tutor! My cie a level exam results just got out and I scored A in chemistry. It is a huge achievement for me, given I scored D on my mock exams. Thank you for your videos which have been very helpful during preparation!
That's brilliant news! Very well done, that's really big progress! 👏
I know this is off topic, but are you expected to know the full balanced autocatalysis equations, or are you expected to work out how to balance it. Balancing it is extremely tricky with the CO2 involu
Involved
And by know I mean completely remember the balanced equations off by heart
Good question.
I'd recommend remembering the beginnings of the half Equations
So MnO4^1- --> Mn2+
C2O4^2- --> CO2
And then you balance them and add then together
Less to remember and the MnO4^1- Equation is relevant elsewhere too
Hi sir thanks for the video. I have an unrelated question if you’d be so kind to help. When do you you know when to use delta s = rlnk compared to delta s = rtlnk
One equation has the temperature in it, in some questions you need to use the one including temperature but I’m not sure when. Do your exclude temperature when the temperature is room temp I.e standard conditions. Thanks.
I'm a bit surprised youre seeing both! The more common equation you will see written is delta G = -RTln(K). Using the equation delta G= delta H - T*delta S we can say that at equilibrium delta S = (delta H)/T + Rln(K). If delta H = 0 this gives delta S = R*ln(K). It is not really of interest to relate this equation with delta S = nR*ln(V2/V1) since these equations account for the changes in entropy of different processes.
@@chemistrytutor
Thanks for the explanation, so when would we use the one without the temperature. I had seen a question but it didn’t say that delta h was zero, but they still excluded the temperature from the equation in the calculation. Temperature was 298K.
@@st56767 did they give you some other clue such as its at equilibrium maybe?
Is it edexcel that you do? They are often quite tricky about only giving subtle clues about how to approach their questions