Consider:

Question

C7 H16(L) + 11 O2 (G) yields 7 CO2 + 8 H2O (L)
delta Hreaction = -4130 kJ

How much energy is released when 2,000 moles of C7 H16 is combusted?

Answer 1

4130 kJ for 1 mole. How much for 2000 moles.

Answer 2

so i would set the problem up like this....
4130kJ/1 mole = xkJ/2000 moles

???

Answer 3

yep

Answer 4

i got 2.065 kJ/mole

Answer 5

you shouldve got a bigger answer and ur solving for the kj not kj/mol. remember you have to multiply the 2000 moles by the 4130 kj/mol to get rid of the mole.

Answer 6

ok so then i set it up wrong
it should be

4130 kj/1 mole = 2000 moles/kj

and that time i got 8260000

i don't know if that is right because the kj would cancel out too

Answer 7

you had it set up right before. ur messing up the algebra. you were solving for the x kj so in order to do that you would have to multiply both sides by the 2000 moles. the moles and 200o would cancel on one side and just the moles on the other. but your number is correct. if you want a better explanation fire away

Answer 8

ok so

(2000moles/1)(4130kj/1mole) = (kj/2000 moles)(2000 moles/1)

(2000)(4130kj) = kj

now what?

Answer 9

now you just multiply them. the number you had before was right just not the whole cancelling out stuff.

Answer 10

ok that's where i got the number 8260000kj=kj

uuuggggh i don't know what im doing wrong!!