HOW WAS CHEMISTRY P42 MAY/JUNE 2017 (POLL)

[Irfanhaider0533]

No it went like this:
60cm3 of some concentration of naoh reacted with the gases. It was 0.03 moles i think. And the excess was titrated with H+ giving 0.0054 moles. So the moles that rwacted with the gases were 0.03-0.0054

 

[HamzaMK_MLG]

Guys, in the 2chlorobutane did you draw Sn1 or Sn2? I kniw that secondary can go either way, but I want to be sure.... The paper was really hard tho, but I am losing like 17 marks only. God damn that 10 marks organic ques...

Also why were the amino acids so close in the last question?

 

[Irfanhaider0533]

I think it was the transition state one i have forgotten its name. Because both of the reactants were in the rate equation

 

[Irfanhaider0533]

For the amino acid one i wrote that it was the whole phe tyr or whatever it was so it was almost isoelectronic

 

[Shafin Ahmed]

No it went like this:
60cm3 of some concentration of naoh reacted with the gases. It was 0.03 moles i think. And the excess was titrated with H+ giving 0.0054 moles. So the moles that rwacted with the gases were 0.03-0.0054

(0.03-0.0054) / 3 = 8.2 x 10^-3

 

[HamzaMK_MLG]

For the amino acid one i wrote that it was the whole phe tyr or whatever it was so it was almost isoelectronic

which amino acid was closest to the + terminal?

 

[darks]

which amino acid was closest to the + terminal?

tyr it was.. due to most negative charge.

 

[blazesparrowx]

What was the answer for the rate

 

[Yo-BKC]

Keq3= kstab2/ kstab 1
lattice energy was -2280 KJ
Delta G was -111.92
Delta H was 8
PH of amino acid was 5.43

Agar yeh answers sahi nikle tau allah tumhe hajj karaye

 

[Irfanhaider0533]

(0.03-0.0054) / 3 = 8.2 x 10^-3

THat was the answer to the next part

 

[Qaussain]

gar yeh answers sahi nikle tau allah tumhe hajj karaye

Sir ik sath Hajj pe chaleinge

 

[Mashruk Anim]

w

I got 81 too
It's because we wrote our product as NaHSO3
Technically, that product isn't wrong, but then I didn't get an acid corresponding to Mr 81, so I'm guessing that's gone all wrong.
6 marks outta the window urgh
Here's hoping they at least consider something out of it

we'd get partial marks and ecf i hope :'(

 

[blazesparrowx]

What was the answer for the rate

Anyone?

 

[Irfanhaider0533]

Anyone?

5.33

 

[Atimahs]

What did u all get for n in the transition element question? I got n as 2, 1 and 0.

 

[Irfanhaider0533]

I got 1,2,3

 

[darks]

Carbon 13 Nmr one was 4,3 & 2 peaks right?
Also what was the product of benzene structure with hcl.. The only thing i did was change nh2 part to nh3+

 

[blazesparrowx]

Carbon 13 Nmr one was 4,3 & 2 peaks right?
Also what was the product of benzene structure with hcl.. The only thing i did was change nh2 part to nh3+

There wasn't any nmr, no?

 

[darks]

There wasn't any nmr, no?

paper 42!! how is everyone saying there was no NMR. I mean there were no peaks to study but they asked to predict the peaks a certain compound would give on carbon 13 nmr spectrum. And then told to alter the structure to give structures with less peaks...

 

[blazesparrowx]

Yes, actually i vaguely remember this question, but didn't they just ask us to draw the structures out, definitely no numbers involved in the answers