Question

The heat of combustion of carbon to co2, is
-393.5 kJ/mol. The heat released upon formation of
35.2 g of Co2, from carbon and oxygen gas is
(1) -630 kJ
(2) -3.15 kJ
(3) -315 kJ
(4) +315 kJ​

Answer 1

Answer:

Correct option is

C

-315 kJ/mole

Heat of combustion for 1 mole of CO

2

is −393.5KJ

Number of moles in 35.2g of CO

2

=

44

35.2

=0.8mole

Thus heat of combustion for 0.8 mole of CO

2

is −393.5×0.8=−315KJ