help with a maths chemistry question

To find how much propane had been used the student weighed the camping stovebefore and after the experiment. The mass of the camping stove decreased by 6.0 g. Using this information and your answer to part 7(a)(i), calculate the energy in kJreleased when 1 mole of propane burns. Relative formula mass (Mr) of propane = 44.

the answer for 7(a)(i) was 148050J

Reply 1

Pigster

20

Delta H = - Q / n

Delta H = value you want (in kJ mol-1)

Q = energy (in kJ, i.e. convert)

n = amount (of propane, in mol)

If you're GCSE, don't panic, every question of this type is essentially the same, just get more practice.

If you're A-level, start panicking, you should have known this last year.

Reply 2

username1490724

16

Original post by Moodicrus

To find how much propane had been used the student weighed the camping stovebefore and after the experiment. The mass of the camping stove decreased by 6.0 g. Using this information and your answer to part 7(a)(i), calculate the energy in kJreleased when 1 mole of propane burns. Relative formula mass (Mr) of propane = 44.

the answer for 7(a)(i) was 148050J

6/44=0.136mol<->148050J
1mol<->1088602.941J
problem solved!

Reply 3

Moodicrus

OP

10

thanks guys :thumbsup: