VCE Chemistry Question Thread

[Elizawei]

Yes, and also that it isn't directly involved in the reaction, as it does not change the product in anyway.

Yeah and it's usually a dehydration agent yeah?

[Syndicate]

Yeah and it's usually a dehydration agent yeah?

Yes, as it would also result in a greater yield of ester.

[Elizawei]

Yes, as it would also result in a greater yield of ester.

Thanks!

[blacksanta62]

Hello, I need some help with this questions:
-In the production of aspirin, why is H2SO4 used as a catalyst? And how can we prove it's the catalyst?

Thanks

[Swagadaktal]

Hello, I need some help with this questions:
-In the production of aspirin, why is H2SO4 used as a catalyst? And how can we prove it's the catalyst?

Thanks

H2SO4 speeds up the esterification reaction between an alkanol and carboxylic acid specifically (my guess would be that tbh but if someone has a better answer pls chime in here)
We can prove it's a catalyst by removing it from the reaction, we would observe the same reaction occurring but at a much slower rate (the same reaction)

[lzxnl]

H2SO4 speeds up the esterification reaction between an alkanol and carboxylic acid specifically (my guess would be that tbh but if someone has a better answer pls chime in here)
We can prove it's a catalyst by removing it from the reaction, we would observe the same reaction occurring but at a much slower rate (the same reaction)

To show that it's a catalyst, you also have to show that it's unused throughout the reaction.

[Swagadaktal]

To show that it's a catalyst, you also have to show that it's unused throughout the reaction.

Yoo my teacher wouldn't accept that answer in a sac soooo

[Mhysa]

Hi
Noob question but how many hydrogen environments are in this molecule?
I thought there were three but the question states otherwise (four?) :/

[jyce]

Hi
Noob question but how many hydrogen environments are in this molecule?
I thought there were three but the question states otherwise (four?) :/

The CH₂ environments on the "bottom" of the molecule are closer to the hydroxyl groups than are the CH₂ environments on the "top". Therefore, you have four hydrogen environments:
1. CH₂ bottom
2. CH₂ top
3. CH
4. OH

[jyce]

Yoo my teacher wouldn't accept that answer in a sac soooo

As lzxnI said, you'd need to show both that:
a) the acid speeds up the rate of ester production
b) the acid's concentration doesn't change (i.e., is not consumed).

[Swagadaktal]

As lzxnI said, you'd need to show both that:
a) the acid speeds up the rate of ester production
b) the acid's concentration doesn't change (i.e., is not consumed).

How would you show it?
I wrote out reactions and wrote an explanation beneath it but it wasnt accepted.
Maybe I did my reaction wrong - people got the answer right for stating that by removing the catalyst the reaction will still occur, but with the catalyst would increase the rate of reaction

[jyce]

How would you show it?
I wrote out reactions and wrote an explanation beneath it but it wasnt accepted.
Maybe I did my reaction wrong - people got the answer right for stating that by removing the catalyst the reaction will still occur, but with the catalyst would increase the rate of reaction

Do you mean how could you show it experimentally? You could show a) using UV-vis. spec., and b) using volumetric analysis.

[Swagadaktal]

Do you mean how could you show it experimentally? You could show a) using UV-vis. spec., and b) using volumetric analysis.

Ahh that makes sense
thanks man

[Mhysa]

Can Sodium Hydroxide be used a catalyst in the reaction between triglycerides and alkanols?
Also can someone please help me with the attached mcq

[Mhysa]

ethanol is a biochemical fuel so why is c correct?