A Level Chemistry - Organic mark scheme (OCR A)

Watch
Silxnt1
Badges: 15
Rep:
?
#1
Report Thread starter 8 months ago
#1
When referring to catalysts that accompany chemical reactions, particularly in organic chemistry, is it necessary (in the exam) to state whether the acid catalyst, if applicable, is concentrated/dilute? Would you still get the marks if you just mentioned the acid catalyst alone?
(For example, if, for the nitration of benzene, you just said HNO3 and H2SO4 instead of conc. HNO3 and conc. H2SO4, would you still get the same amount of marks?)

And what about for whether or not a reagent is in excess?
0
reply
Pigster
Badges: 20
Rep:
?
#2
Report 8 months ago
#2
(Original post by Silxnt1)
When referring to catalysts that accompany chemical reactions, particularly in organic chemistry, is it necessary (in the exam) to state whether the acid catalyst, if applicable, is concentrated/dilute? Would you still get the marks if you just mentioned the acid catalyst alone?
(For example, if, for the nitration of benzene, you just said HNO3 and H2SO4 instead of conc. HNO3 and conc. H2SO4, would you still get the same amount of marks?)

And what about for whether or not a reagent is in excess?
If you read the spec. and mark schemes, you'll quickly be able to make a list of where conc is required.

I'll give you this one for free:

6.1.1(d) the electrophilic substitution of aromatic compounds with:
(i) concentrated nitric acid in the presence of concentrated sulfuric acid

With regards to your second questions. Do the same thing.

Again, here's a free one:

6.2.1(b) the preparation of:
(i) aliphatic amines by substitution of haloalkanes with excess ethanolic ammonia and amines

You could always just do a search on the spec for the words "concentrated" and/or "excess" and see what pops up.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Do you think receiving Teacher Assessed Grades will impact your future?

I'm worried it will negatively impact me getting into university/college (180)
44.33%
I'm worried that I’m not academically prepared for the next stage in my educational journey (45)
11.08%
I'm worried it will impact my future career (32)
7.88%
I'm worried that my grades will be seen as ‘lesser’ because I didn’t take exams (86)
21.18%
I don’t think that receiving these grades will impact my future (40)
9.85%
I think that receiving these grades will affect me in another way (let us know in the discussion!) (23)
5.67%

Watched Threads

View All