How Was Chemistry Paper 22, MAY/JUNE 2017?

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What was the answer for how's the percentage decomposition affected by increasing temperature[/QUOTE

That question.....................................

 

[Hassan (SHT)]

I think these were the points
Increase in temp will shift the equilibirum towards the RHS
Because forward reaction and endo
Hence %of HBr decomposition increase

 

[darks]

I think these were the points
Increase in temp will shift the equilibirum towards the RHS
Because forward reaction and endo
Hence %of HBr decomposition increase

this might be good enough for 2 marks. It clearly asked for le chatlier's principle as far as i can remember.

 

[darks]

I wrote structural formula of eyhanoic acid and methyl methanaote instead of.their names will it be acceptable?

Sorry but no. When names are asked, they are the only option you have.

 

[Alpharaptor]

What was the answer for how's the percentage decomposition affected by increasing temperature

the rate increases

 

[Talha Jameel]

this might be good enough for 2 marks. It clearly asked for le chatlier's principle as far as i can remember.

Thats fine for 3 marks

 

[Talha Jameel]

What was the nucleon number for Fe? I forgot xD
Secondly what was the answer to high boiling point of unchained hydrocarbons?

 

[darks]

What was the nucleon number for Fe? I forgot xD
Secondly what was the answer to high boiling point of unchained hydrocarbons?

Unbranched hydrocarbons have a higher boiling point. In unbranched hydrocarbons, molecules are closer together compared to branched hydrocarbons. Unbranched hydrocarbons have stronger V.W. forces between them which are harder to overcome compared to branched hydrocarbons, so unbranched hydrocarbons have a higher boiling point. Just my answer. Not sure if good enough for 2 marks.

 

[Talha Jameel]

Unbranched hydrocarbons have a higher boiling point. In unbranched hydrocarbons, molecules are closer together compared to branched hydrocarbons. Unbranched hydrocarbons have stronger V.W. forces between them which are harder to overcome compared to branched hydrocarbons, so unbranched hydrocarbons have a higher boiling point. Just my answer. Not sure if good enough for 2 marks.

I wrote that unbranched can overlap each other, increasing the molecular forces and bla bla.... lets see

 

[Talha Jameel]

Nucleon number of Fe, anyone?? xD

 

[Hassan (SHT)]

Unbranched hydrocarbons have a higher boiling point. In unbranched hydrocarbons, molecules are closer together compared to branched hydrocarbons. Unbranched hydrocarbons have stronger V.W. forces between them which are harder to overcome compared to branched hydrocarbons, so unbranched hydrocarbons have a higher boiling point. Just my answer. Not sure if good enough for 2 marks.

These were the simple points
Unbranched structure have larger surface area
Therefore more vanderwaal forces hence higher amount of energy needed to overcome these forces

 

[Hassan (SHT)]

What was the answer for that no need of total pressure ?

 

[sarmadimran]

What was the answer for that no need of total pressure ?

Equal number of moles of gas present on both sides of equation

 

[sarmadimran]

Nucleon number of Fe, anyone?? xD

58 I guess

 

[Error Syntax]

What was the answer for that no need of total pressure ?

what did you wrote?

 

[Error Syntax]

What did you guys wrote in that Bond strength effecting the decomposition percentages?

 

[sarmadimran]

What did you guys wrote in that Bond strength effecting the decomposition percentages?

Hbr bond strength greater than HI due to short bond length and greater overlap of orbitals hence electrons are closer to nucleus

 

[Error Syntax]

Hbr bond strength greater than HI due to short bond length and greater overlap of orbitals hence electrons are closer to nucleus

yeah i wrote the same thing that HBr has greater bond energy than HI because HI has a greater bond length which reduces the attraction of nucleus with the bonded electrons and so with the same amount of energy the HI bonds will break in more amount as compare to HBr due to lower requirement of energy for HI bonds to break.

 

[Zaki ali asghar]

Expecting around 54-55,i screwed up the easiest part to calculate isptope mass where answer was required to 6 sig figs.What was its answer?

 

[Error Syntax]

Expecting around 54-55,i screwed up the easiest part to calculate isptope mass where answer was required to 6 sig figs.What was its answer?

I dont know exactly but the answer was around 10.9940 something this isnt an accurate value its just my rough estimate of what i remember.