Chemistry: Post your doubts here!

[♣♠ Magnanimous ♣♠]

only acid reacts with sodium to give hydrogen isnt it?

but new edition the orange book.. chapter 16 page 240.. here i can see that alcohol reacts with sodium to give HYDROGEN! and that one mole ..
so how D

 

[♣♠ Magnanimous ♣♠]

1 mol of either -COOH or -OH gives .5mols of hydrogen
therefore there should be either 2 OH groups or 2 COOH groups or one from each
as a result we end up with D!

but if we take reac A than too we can get one mole isn't it!

 

[♣♠ Magnanimous ♣♠]

THAT'S A PRINTING MISTAKE!!!!!!1
TRY BALANCING THAT REACTION

Yeah!! I was wondering that only

 

[♣♠ Magnanimous ♣♠]

what is this --> CH3CH(OH)CH3
an alcohol or anything else?

 

[mehria]

what is this --> CH3CH(OH)CH3
an alcohol or anything else?

it is an alcohol

 

[♣♠ Magnanimous ♣♠]

it is an alcohol

ok

 

[Metanoia]

View attachment 43831

Ans is A.
Based on bond energy C-Cl would be broken.

C-F and C-H bond would not be broken.

 

[♣♠ Magnanimous ♣♠]

Ans is A.
Based on bond energy C-Cl would be broken.

C-F and C-H bond would not be broken.

sorry!! answer is wrong

 

[IGCSE13]

http://papers.xtremepapers.com/CIE/...d AS Level/Chemistry (9701)/9701_w07_qp_1.pdf. Q 9 , 32 and 37 please

 

[Metanoia]

View attachment 43797My answer is C but the answer is D so anyone explain please!

* Feeling Lazy *
Look it Is Slow Meaning it has Higher Activation Meaning It will Have Longer Hump or Whtever is that thingy..! The other One has A fast Reaction Meaning Lower Activation Energy ( that Curved Part Below The First One) So D!

I'm sorry, but the explanation is not correct.

If we look carefully, the activation energy of the 1st step is more than the activation energy of the 2nd step for both options C and D.

The correct approach is to realise there are two humps (2 step reaction), so either C or D.
Then we need to recognise it forms a more stable product, i.e exothermic, so answer is D.

 

[Metanoia]

sorry!! answer is wrong

Oh, I'm surprised. What is the supplied answer?

 

[♣♠ Magnanimous ♣♠]

Oh, I'm surprised. What is the supplied answer?

it is C

 

[♣♠ Magnanimous ♣♠]

D should be the correct answer!

The answer is C

 

[Metanoia]

it is C

Oh, thats right, i apologised.

Option A is actually C-F bond broken.
For option C, it is the C-Cl bond broken.

So its is option C, but using the explanation I mentioned in post #9124

 

[♣♠ Magnanimous ♣♠]

Oh, thats right, i apologised.

Option A is actually C-F bond broken.
For option C, it is the C-Cl bond broken.

So its is option C, but using the explanation I mentioned in post #9124

thanks

 

[♣♠ Magnanimous ♣♠]

can i know the year please?

2003

 

[♣♠ Magnanimous ♣♠]

2003 what session may or oct?

may june!

 

[♣♠ Magnanimous ♣♠]

it's not there!!!!!!!

ques 27 see it

 

[Metanoia]

D should be the correct answer!
becoz faster the reaction, lower the Ea and lower the hump and since reaction 2 is faster it should have a lower hump!

You are right in that in is option D and not C, but the approach is a bit risky.

Hmm...are you comparing the 2nd hump of option C vs the 2nd hump of option D? That would be a dangerous approach.

At most we should be comparing the
1) 1st hump of option C vs 2nd hump of option C
or
2) 1st hump of option D vs 2nd hump of option D

And in both option C and D, the 1st step is slower than 2nd step, so we can't decide between C or D just by this alone.

 

[♣♠ Magnanimous ♣♠]

SORRY

hahaha