AQA AS 2016 - CHEM1 (Resit) Unoffical Mark Scheme

for the balancing equation questions, if you got the other products right but they aren't balanced, do you get 1/2?

that's what i put my g, i think you have to talk about electron clouds and how at any given time one side is less neg and one side is more neg so attract other electron clouds etc...

Here is my unofficial mark scheme. Anything in bold I am not sure if it's right. So if you have any idea then please tell me so i can add it! If i have missed anything out then aslo let me know!

Section A

1.
a) Relative Atomic mass Definition
b) Magnetic Field
c) - Ions accept electrons -Current is formed which is proportional to abundance
d) Something like 28.065 for the RAM
e) Similarity= Peaks still at original m/z values becuase +1 ions are still formed. Difference - Peaks at half the m/z values becasue high energy electrons will produce +2 ions

2. (Can't rmember what topic this was. I think it was about Van Der Waals)
a) -Electron Density randomly shifts -Creating areas of +ve and -ve charge on molecule - Attraction between molecules which is intermolecular force/VDW
b) O-H bond big electronegative difference allows for hydrogen bonds. Hydrogen bonds are stronger than VDW.
c) The Se molecule is larger? This means the VDW forces are stronger between molecules

3. (Questions about Alkanes?)
a) Group is alkane
b) 2,2,4 - trimethylpentane (might accept 2,4,4 - trimethylpentane)
c) C₈H₁₈ + 12.5O₂ ------> 9H₂O + 8CO₂
d) but-1-ene
e) C₁₄H₃₀
f) Isomers question. Chain isomer = H₂C=C(CH₃)₂ Postion isomer = But-2-ene Functional Isomer = Cyclic Alkane so basically a square skeltal formula

4. (The weird reactions and the shapes question?)
a) Balancing equation I couldn't remember
b) Cu₂(OH)₂CO₃ + 4HCl -----> 2CuCl₂ + 3H₂O + CO₂
c) Effervescense
d) Something like Cu₃O₈H₂C₂
e) Shapes question - SF₆ = Octohedral , 90 degrees SF₄ = I thought it was trigonal bipyramidal with the lone pair in the horzontal plane with angles of 120 degrees and 90 degrees but others saying it was tetrahedral with and of 107 degress

Section B

5. (Period 3 stuff)
a) - Ionisation energies increase -Increasing proton number - Similar Shielding -Attraction between outer electron and nuclues gets stronger -The bigger nuclear charge reduces atomic radius (I don't think this point is needed)
b) -Silicon has highest melting point. -Because of macromolecular/Giant covelant structure. -Strong covelant bonds throughout structure. -Requires high amounts of energy to break.
c) The elements that you could say were Aluminuim because removing electron form 3p shell and Sulfur because of pair repulsion.
d) -Element Y is Sulphur. -Large jump in eneries from 6^th to 7^th ionisation enegies -So 7^th electron in inner shell so sulphur must be the element Y.

6. (Calculations)
a) 0.113m³ (3 sig figs needed)
b) 1065 Kg or 1.065x10⁶ g
c) Percentage yield = 49.3%
d) Method 1 because its 100% atom economy. Only producing one product.

I remember there was a 2 marker on the type of cracking needed to make X
thanks for this btw!!

Here is my unofficial mark scheme. Anything in bold I am not sure if it's right. So if you have any idea then please tell me so i can add it! If i have missed anything out then aslo let me know!

Section A

1.
a) Relative Atomic mass Definition
b) Magnetic Field
c) - Ions accept electrons -Current is formed which is proportional to abundance
d) Something like 28.065 for the RAM
e) Similarity= Peaks still at original m/z values becuase +1 ions are still formed. Difference - Peaks at half the m/z values becasue high energy electrons will produce +2 ions

2. (Can't rmember what topic this was. I think it was about Van Der Waals)
a) -Electron Density randomly shifts -Creating areas of +ve and -ve charge on molecule - Attraction between molecules which is intermolecular force/VDW
b) O-H bond big electronegative difference allows for hydrogen bonds. Hydrogen bonds are stronger than VDW.
c) The Se molecule is larger? This means the VDW forces are stronger between molecules

3. (Questions about Alkanes?)
a) Group is alkane
b) 2,2,4 - trimethylpentane (might accept 2,4,4 - trimethylpentane)
c) C₈H₁₈ + 12.5O₂ ------> 9H₂O + 8CO₂
d) but-1-ene
e) C₁₄H₃₀
f) Thermal Cracking. High temp and high pressure
g) Isomers question. Chain isomer = H₂C=C(CH₃)₂ Postion isomer = But-2-ene Functional Isomer = Cyclic Alkane so cyclicbutane

4. (The weird reactions and the shapes question?)
a) Balancing equation I couldn't remember
b) Cu₂(OH)₂CO₃ + 4HCl -----> 2CuCl₂ + 3H₂O + CO₂
c) Effervescense
d) Something like Cu₃O₈H₂C₂
e) Shapes question - SF₆ = Octohedral , 90 degrees SF₄ = I thought it was trigonal bipyramidal with the lone pair in the horzontal plane with angles of 120 degrees and 90 degrees but others saying it was tetrahedral with and of 107 degress

Section B

5. (Period 3 stuff)
a) - Ionisation energies increase -Increasing proton number - Similar Shielding -Attraction between outer electron and nuclues gets stronger -The bigger nuclear charge reduces atomic radius (I don't think this point is needed)
b) -Silicon has highest melting point. -Because of macromolecular/Giant covelant structure. -Strong covelant bonds throughout structure. -Requires high amounts of energy to break.
c) The elements that you could say were Aluminuim because removing electron form 3p shell and Sulfur because of pair repulsion.
d) -Element Y is Sulphur. -Large jump in eneries from 6^th to 7^th ionisation enegies -So 7^th electron in inner shell so sulphur must be the element Y.

6. (Calculations)
a) 0.113m³ (3 sig figs needed)
b) 1065 Kg or 1.065x10⁶ g
c) Percentage yield = 49.3%
d) Method 1 because its 100% atom economy. Only producing one product.

There was a one marker on how to separate methanol and methanethiol

I said for the second shape question, that it was acting as a Trigonal Bipyramid as it has 4 bonding pairs and 1 lone pair, taking 2.5 from each, so 117.5 and 87.5. the question said bond angle(s)

There wasn't a box for the shape for the second one


Posted from TSR Mobile

Sure that it was 5 pairs so 90/120 - it was in a past paper I did

Sure that it was 5 pairs so 90/120 - it was in a past paper I did

There wasn't a box for the shape for the second one


Posted from TSR Mobile

yeah i know but for the bond angle it said angle(s) so i think it wouldve been 2, what did u put?

The ration was 1:1 for phsophorus to the oxide. So work out the mol of the phsphorus = 220g/124 = 1.774 mol

Then use pV = nRT to find volume. 500 degress celcius (converted to 773K) and 101kPa

V = (1.774 x 8.31 x 773)/101000 = 0.1128 m³ = 0.113 m³

So annoyed at myself, I think I just divided 220g by 31 for the Mr of just P not P4😭😭😭 so that'll be why, was the equation definetly not P+02---> P4O10

Or is it P4+02--->P4010 😩

Here is my unofficial mark scheme. Anything in bold I am not sure if it's right. So if you have any idea then please tell me so i can add it! If i have missed anything out then aslo let me know!

Section A

1.
a) Relative Atomic mass Definition
b) Magnetic Field
c) - Ions accept electrons -Current is formed which is proportional to abundance
d) Something like 28.065 for the RAM
e) Similarity= Peaks still at original m/z values becuase +1 ions are still formed. Difference - Peaks at half the m/z values becasue high energy electrons will produce +2 ions

2. (Can't rmember what topic this was. I think it was about Van Der Waals)
a) -Electron Density randomly shifts -Creating areas of +ve and -ve charge on molecule - Attraction between molecules which is intermolecular force/VDW
b) O-H bond big electronegative difference allows for hydrogen bonds. Hydrogen bonds are stronger than VDW.
c) Fractional Distiallation will sperate these
d) The Se molecule is larger? This means the VDW forces are stronger between molecules

3. (Questions about Alkanes?)
a) Group is alkane
b) 2,2,4 - trimethylpentane (might accept 2,4,4 - trimethylpentane)
c) C₈H₁₈ + 12.5O₂ ------> 9H₂O + 8CO₂
d) but-1-ene
e) C₁₄H₃₀
f) Thermal Cracking. High temp and high pressure
g) Isomers question. Chain isomer = H₂C=C(CH₃)₂ Postion isomer = But-2-ene Functional Isomer = Cyclic Alkane so cyclicbutane

4. (The weird reactions and the shapes question?)
a) Balancing equation I couldn't remember
b) Cu₂(OH)₂CO₃ + 4HCl -----> 2CuCl₂ + 3H₂O + CO₂
c) Effervescense
d) Something like Cu₃O₈H₂C₂
e) Shapes question - SF₆ = Octohedral , 90 degrees -SF₄ = See-Saw shape. Lone pair on the horizontal plane. Angles 90, 120 or 180 degrees. Probably will accept -2.5 degrees off each angle.

Section B

5. (Period 3 stuff)
a) - Ionisation energies increase -Increasing proton number - Similar Shielding -Attraction between outer electron and nuclues gets stronger -The bigger nuclear charge reduces atomic radius (I don't think this point is needed)
b) -Silicon has highest melting point. -Because of macromolecular/Giant covelant structure. -Strong covelant bonds throughout structure. -Requires high amounts of energy to break.
c) The elements that you could say were Aluminuim because removing electron form 3p shell and Sulfur because of pair repulsion.
d) -Element Y is Sulphur. -Large jump in eneries from 6^th to 7^th ionisation enegies -So 7^th electron in inner shell so sulphur must be the element Y.

6. (Calculations)
a) 0.113m³ (3 sig figs needed)
b) 1065 Kg or 1.065x10⁶ g
c) Percentage yield = 49.3%
d) Method 1 because its 100% atom economy. Only producing one product.

I'm such an idiot and didn't realise co2 was formed and put h2co3 and water instead (don't ask).Then I wrote the colour of cucl4 as my observation fml.

I'm such an idiot and didn't realise co2 was formed and put h2co3 and water instead (don't ask).Then I wrote the colour of cucl4 as my observation fml.