OCR F321 - 23rd May

Reply 780

gids

Original post by xI_NICHO_Ix

ideas on grade boundries ? about 50 for an A it was an alright paper overall

what did everyone else think

44-46

Reply 781

rege

what if you spell nucleus wrong!! :frown:

Reply 782

V.sey

Original post by lucy1234

Wasnt the empirical formula

mg2si4o ?

If you meant Mg2SiO4* then yeah. That's what I got anyways... :confused:

Reply 783

Hazel92

10

so far all i know is i lost the 2 marks for disproportionation reaction, i think the mark for the Zn3(PO4)3, at least 1 mark from the last question. so 4 so far.. hope i dont lose anymore, i could really do with 56/60 considering this is my final attempt. :/

Reply 784

sixthformer

cl2 + NaOh --> NaCl + NaClo + H20

this question was 1 mark i'm sure

Reply 785

sixthformer

Original post by Hazel92

so far all i know is i lost the 2 marks for disproportionation reaction, i think the mark for the Zn3(PO4)3, at least 1 mark from the last question. so 4 so far.. hope i dont lose anymore, i could really do with 56/60 considering this is my final attempt. :/

i've lost 5

1 mark for 32 electrons, 1 for chlorate(5) ... wrote the wrong roman numeral, didn't even know i had to learn them, 2 marks for not balancing equations (it didn't ask me to), and 1 mark for a random silly mistake

55/60 i hope :frown:

i know for sure it'll sky drop

Reply 786

rege

Original post by sixthformer

cl2 + NaOh --> NaCl + NaClo + H20

this question was 1 mark i'm sure

It was 2NaOH and 2NaClO

Reply 787

lil_kittie2

it was 44 in january and it was a easier paper then. so hopefully 42!!!

Reply 788

V.sey

Original post by simmyxx

I don't get that question where you had to work out the relative formula...i think it was something like Mg2.6H2O???
Can someone explain that please?!?!?
I know that there is nothing I can do now but there is no harm in knowing
...

Its Just the Ar of all elements added together. It was MgCl2. 6H20

So Mg = 24.3
2 * CL = 2 * 35.5
1 H20 = 18 so 6 of H20 = 108

Add all up = 203.3 I think...

Reply 789

Eat.Sleep.Row.Repeat.

8

I've lost a few marks I think. I got the mole one wrong, I got 1.6x10^-3 rather than ^-2 so my next mark was wrong. So I ended up getting 9.3% rather than 93. So i'll probably lose atleast 1 mark for that. I then messed up the last question because I was panicking due to lack of time. I put that SiO2 was a giant covalent lattice with covalent bonds...then crossed it out *facepalm*. Went on about SiCl4 having more van der waals so it'd have a higher boiling point. Don't know why I did that. I reckon I lost about 8 marks :/ was aiming for 55+ out of 60, but I guess it'll be like 57/60 for full ums. So hopefully I still got 90%+. Just need to nail the next exam!

Reply 790

simmyxx

6

Original post by V.sey

Its Just the Ar of all elements added together. It was MgCl2. 6H20

So Mg = 24.3
2 * CL = 2 * 35.5
1 H20 = 18 so 6 of H20 = 108

Add all up = 203.3 I think...

ohhhh....i dont think that is what i put...but thanks anyways :smile:

Reply 791

Hazel92

10

what happens if you write something irrelevant to the question but also answer the question.. lose marks?
I dont know what i was thinking so i wrote:

as you go across the period the number of protons increase increasing the nuclear charge, this increases the attraction on the outershell electrons pulling it closer to the nucleus. Electron shileding stays same as electrons are added to the same shell.
^^^^^^^^^^^^^^^^^^^^^^this was the irreleveant part. Then I wrote:

SiO2 is a giant covalent structure and has strong covalent bonds that require high energy to break and SiCl4 is a simple molecular struture and has weak van der waals forces between molecules therefore requires less energy to break/ broken easily.

I SHOULDNT HAVE DONE THIS I KNOW, BUT I WAS PUSHED FOR TIME, MISINTERPRETED THE QUESTION THEN REALISED LATER WHEN I CLOSED MY QUESTION PAPER! ARRGH!

Reply 792

V.sey

Original post by rege

It was 2NaOH and 2NaClO

2NaOH but only one NaClO coz u have NaCl product as well!

Reply 793

simmyxx

6

Original post by Hazel92

what happens if you write something irrelevant to the question but also answer the question.. lose marks?
I dont know what i was thinking so i wrote:

as you go across the period the number of protons increase increasing the nuclear charge, this increases the attraction on the outershell electrons pulling it closer to the nucleus. Electron shileding stays same as electrons are added to the same shell.
^^^^^^^^^^^^^^^^^^^^^^this was the irreleveant part. Then I wrote:

SiO2 is a giant covalent structure and has strong covalent bonds that require high energy to break and SiCl4 is a simple molecular struture and has weak van der waals forces between molecules therefore requires less energy to break/ broken easily.

I SHOULDNT HAVE DONE THIS I KNOW, BUT I WAS PUSHED FOR TIME, MISINTERPRETED THE QUESTION THEN REALISED LATER WHEN I CLOSED MY QUESTION PAPER! ARRGH!

Ahhh!!!
I did the same thing...woopsies

Reply 794

V.sey

Original post by Hazel92

what happens if you write something irrelevant to the question but also answer the question.. lose marks?
I dont know what i was thinking so i wrote:

as you go across the period the number of protons increase increasing the nuclear charge, this increases the attraction on the outershell electrons pulling it closer to the nucleus. Electron shileding stays same as electrons are added to the same shell.
^^^^^^^^^^^^^^^^^^^^^^this was the irreleveant part. Then I wrote:

SiO2 is a giant covalent structure and has strong covalent bonds that require high energy to break and SiCl4 is a simple molecular struture and has weak van der waals forces between molecules therefore requires less energy to break/ broken easily.

I SHOULDNT HAVE DONE THIS I KNOW, BUT I WAS PUSHED FOR TIME, MISINTERPRETED THE QUESTION THEN REALISED LATER WHEN I CLOSED MY QUESTION PAPER! ARRGH!

I think they'll ignore your first bit and mark the right part :smile:

Reply 795

rege

Original post by V.sey

2NaOH but only one NaClO coz u have NaCl product as well!

Yup..my bad :biggrin:

Reply 796

broken_glass_heart

Original post by sixthformer

cl2 + NaOh --> NaCl + NaClo + H20

this question was 1 mark i'm sure

anyone else agree this question was 1 mark, let me know, if many people say it was 1 mark then i can edit it on the unofficial mark scheme

Reply 797

lolo-x

Original post by gids

it is Na because the first ionisation was a big difference to the second ionisation. because Na only has one electron on the outer shell. therefore this means the big difference on the first and second ionisation means the second electron was removed from a differ shell

dayyymm. you are right. :smile:

Reply 798

simmyxx

6

I think it was one mark as well???

Reply 799

broken_glass_heart

what asnwers did everyone else get for the no. of moles of HCl and Mg(OH)2? 1 got 0.016 and 0.008 mol, please can someone confirm if this was right or not?

OCR F321 - 23rd May

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you