The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

This discussion is now closed.

Check out other Related discussions

OCR AS Chemistry [Breadth] Mon 20th May Unofficial markscheme

Scroll to see replies

Original post by fares22
I got 90 kJ per mol


I got 90 as well but it was formation so I put -90. I have no idea if thats right or not. I used the right equation and got +90.
Yh it was weird. but +90 was the only way the equation made sense tbh. What did you get for the table of the elements?
Original post by dylan_sian
i got +90
I think it was 89KJ
Wait where you supposed to say what it was lol whoops I drew the structures
Original post by grebnesieH
I did the same. The 3rd was mid-chain so it was a secondary alcohol so its ketone
xxxx
I replaced the hydroxl group with the a COOH for 1st, None for second and Ketone for 3rd

Original post by TheFlash...cards
Wait where you supposed to say what it was lol whoops I drew the structures
Original post by TheFlash...cards
Wait where you supposed to say what it was lol whoops I drew the structures

No you only had to draw the structure lol.
Original post by fares22
I replaced the hydroxl group with the a COOH for 1st, None for second and Ketone for 3rd

i did exactly the same
Original post by fares22
Yh it was weird. but +90 was the only way the equation made sense tbh. What did you get for the table of the elements?

Your probably right, formation can be endothermic as well (i think).

I got Iron and Krypton for table
xxxx
What did people say about about that ammonium bromide q

I did the bromide bit, u add Ag(NO3), cream precipitate

Ag + Br- ---> AgBr

No idea about the cation test, i said somet about a flame test, what did everyone else say?
Did you guys get 10 for volume mixture
wasnt it Se cos the proton number was 34 and the charge was 2- hence giving it 36 electrons?
Original post by dylan_sian
What did people say about about that ammonium bromide q

I did the bromide bit, u add Ag(NO3), cream precipitate

Ag + Br- ---> AgBr

No idea about the cation test, i said somet about a flame test, what did everyone else say?

ohh i forgot to write the equation. damn
Original post by dylan_sian
What did people say about about that ammonium bromide q

I did the bromide bit, u add Ag(NO3), cream precipitate

Ag + Br- ---> AgBr

No idea about the cation test, i said somet about a flame test, what did everyone else say?


The ammonium test was with red litmus paper and it turned blue because it was alkaline or something i think
Original post by dylan_sian
What did people say about about that ammonium bromide q

I did the bromide bit, u add Ag(NO3), cream precipitate

Ag + Br- ---> AgBr

No idea about the cation test, i said somet about a flame test, what did everyone else say?


You needed to add sodium hydroxide and test the gas with red litmus paper. If it was present, it turns it blue
I put Mn and Br. probably wrong.
Original post by dylan_sian
wasnt it Se cos the proton number was 34 and the charge was 2- hence giving it 36 electrons?
Original post by fares22
I put Mn and Br. probably wrong.


i thought no. protons =no. electrons

unless it was an ion??.
How did you work out the last question about the molecular formula for the haloalkane?
yh thats what i did.
Original post by grebnesieH
i thought no. protons =no. electrons

unless it was an ion??.

Related discussions

Latest

Trending

Trending

Articles for you