Competition - post a photo you've taken of nature >>

2016 IGCSE Chemistry Paper 2 Unofficial Mark Scheme 2016

Scroll to see replies

Thanks for making this mark scheme!!!

I think it was iron + sulfuric acid (I think)

Also, for ionic bonding, it is okay to write 'the electrostatic attraction between oppositely charged ions' ...?

Reply 161

anon138

Original post by Abodee1

How does he know when the crystallisation point is reached? i wrote take a sample and let it cool in air and if it crystallises then the point has been reached.

And for the aluminium mass i got 180g.

Crystallisation point is reached when you get a bit on the end of a glass rod and it crystallises on the glass rod

Reply 162

aaljhfgahsj

Original post by Abodee1

It was my last exam for this year :P i have done bio, chemistry and maths in year 10 and going to do 5 other subjects next year (11).What subjects are left for you guys?

Just physics on friday then they're ALL FINISHED !!!!!!!!!!! fml its been 1 1/2 months

Reply 163

Cheekymonkey2311

for some strange reasoni missed the question where you had to add the electrons for sodium or something, does anybody know how many marks that was?

(edited 7 years ago)

Reply 164

y64654

did anyone else get 0.00625? for the one which is 0.625 in the mark scheme can someone explain?

Reply 165

rcmack

Original post by Emilia1479

Thanks for making this mark scheme!!!

I think it was iron + sulfuric acid (I think)

Also, for ionic bonding, it is okay to write 'the electrostatic attraction between oppositely charged ions' ...?

yes! forgot to include that in the markscheme, thanks :biggrin:

Reply 166

drogon

Original post by Niclewis

nope you're wrong once again. It produces carbon monoxide AND carbon AND water AND carbon dioxide

lol wtf that's wrong

Reply 167

Abodee1

Original post by Cheekymonkey2311

for some strange reasoni missed the question where you had to add the electrons for sodium or something, does anybody know how many marks that was?

3 marks. Including charges.

Reply 168

Nurne

But-1-ene goes colourless, alkanes stay orange.

Reply 169

Nurne

Original post by Nurne

But-1-ene goes colourless, alkanes stay orange.

But-1-ene + Bromine -> Dibromobutane
C4H8+Br2->CH3-CH2-CBr2-CH3

Reply 170

outgoingpopcorn

Wait was there 3 parts on the last question? I thought there was only 2.

Reply 171

F0X

Original post by rcmack

Edexcel iGCSE Chemistry Paper 2C 15 June, sorry should have specified in the question...
1c) Colourless liquid is solution

Are you sure? Although the salt dissolved, the sand didn't... Isn't sand in water a suspension?

1d) Crystallisation point is when crystals begin to form

This wasn't in Question 1, but in a later question (maybe Q3 or so)

7a) 2.75g
7b) 0.0625mol
7c) 1500 cm3

This was from Q8, not Q7, and also there was no part c), and 1500cm3 was the answer to part b).

Reply 172

johannesburg

were they two chemistry jokes or not idk (dehydrated/basic)

Reply 173

rcmack

Original post by johannesburg

were they two chemistry jokes or not idk (dehydrated/basic)

huh?

Reply 174

Hsevras

I don't recall there being an answer with 0.0625 moles as an answer. I thought the two answers were 2.75g and 1500cm^3. I did put 0.0625 in my working, if that is what they were after... Also what would 130+ be in terms of grade boundaries. The average from 2013-16 is 121 for an A and 141 for an A*. I'd assume A will be 127... would I be roughtly correct?

Reply 175

Lelanor

Original post by y64654

did anyone else get 0.00625? for the one which is 0.625 in the mark scheme can someone explain?

I can't remember what I got, but did you convert between cm^3 and dm^3 correctly?
(dm^3 > cm^3 multiply by 1000
cm^3 > dm^3 divide by 1000)

(edited 7 years ago)

Reply 176

Debby 123

For the Iron (II) and Iron (III) question, could you just say the colour or do you need to put the word precipitate as well?

Reply 177

Nurne

For 2b) It was Iron+ Sulphuric acid -> Iron Sulphate + Hydrogen

And for 4b not meaning to be nit picky but it's Pipette you accidentally put double p.

(edited 7 years ago)

Reply 178

jamesj477

Original post by Nurne

For 2b) It was Iron+ Sulphuric acid -> Iron Sulphate + Hydrogen

And for 4b not meaning to be nit picky but it's Pipette you accidentally put double p.

For 4B didn't it say what you use to measure the KOH, so wouldn't it be measuring cylinder? Or did I just misread the question lol

Reply 179

pendos

Original post by jose99

Don't think you'll get the marks for smaller chains being more useful - they aren't. They are simply in higher demand.

I think u need to say why they're in higher demand...because they are more volatile
Also because they produce alkene are produced to make polymers which can be used to make plastics

Posted from TSR Mobile