OCR Chemistry B F331 Chemistry for Life (13-01-2012)

I had c1 this morning, how come you have c1 and c2 in the same day ? F. Maths or retake ?

I had a cheese bagguete for lunch

I lost the marks on the functional groups :'(
and I messed up the emissions questions,
and Im pretty sure I lost other marks by accident </3

so I guess, around 10 - 13 marks lost </3
and an A is probably going to be around 54, as it was a fairly easy paper (

this was soo much harder than any past paper !!!

I lost the marks on the functional groups :'(
and I messed up the emissions questions,
and Im pretty sure I lost other marks by accident </3

so I guess, around 10 - 13 marks lost </3
and an A is probably going to be around 54, as it was a fairly easy paper (

Something about particulates question?
I wrote: incomplete combustion than wrote about nitrogen oxides forming photochemical smog

Does anyone know when the exam results are out?

It's just incomplete combustion. This came up in the old spec paper from Jan 2008. 1 mark for saying incomplete, 1 mark for saying combustion.

1. Biofuel is made from non-food parts of plants
Name one reason for using non-food plant matter as biofuel. (1)
Furfural is a fuel with an aldehyde functional group. Name two other functional groups on the furfural molecule (2)
A student calculated the enthalpy change for combustion of furfural. he measured the change in weight of the burner and the change in temperature of the water, name three other factors the student would need to know to calculate the deltaH (3)
the enthalpy of the bonds in the reactants is 7800(please clarify)kj and the enthalphy of the bonds in the reactants is 9880(please clarify) Calculate the Enthalpy change of combustion (1)
The student's value for the deltaH and the one from the databook are very different. Aside from heat losses suggest why this could be the case(3or 4)

That's what I remember question 1 as.

(a) Wrote something about 3rd world countries not starving or something lol!
(b) ether and alkene
(c) specific heat capacity of water, volume of water heated, Mr of furfural.
(d) -2xxx kJmol-1 (can't remember exact digits)
(e) incomplete combustion, experiment may not have been performed under exact standard condition, bond enthalpy values are taken when in their gaseous state

I'm pretty sure that nothing is wrong there, but please correct me if I've made any mistakes!

1. Biofuel is made from non-food parts of plants
Name one reason for using non-food plant matter as biofuel. (1)
Furfural is a fuel with an aldehyde functional group. Name two other functional groups on the furfural molecule (2)
A student calculated the enthalpy change for combustion of furfural. he measured the change in weight of the burner and the change in temperature of the water, name three other factors the student would need to know to calculate the deltaH (3)
the enthalpy of the bonds in the reactants is 7800(please clarify)kj and the enthalphy of the bonds in the reactants is 9880(please clarify) Calculate the Enthalpy change of combustion (1)
The student's value for the deltaH and the one from the databook are very different. Aside from heat losses suggest why this could be the case(3or 4)

That's what I remember question 1 as.

Last question was State 3 reasons why the Students value for deltaH and one from the data book are very different; Aside from heat lost. (3 Marks)

I Put that you have to consider:
1. Human error; Misreading of the tempature increase.
2. Unbrunt Fuel; Lower ratio of heat to fuel.
3. Value from the data book is from average bond energy therefore could be higher then the ture value.

What does anyone else think of that question?