Question

In an industrial process ethanol C2H60 burns with O2 to produce heat. Each mole of ethanol produces 8842 joules during the reaction.

C2H5OH (1) + 3 O2(g) 2 CO2(g) + 3 H2O(0) + 8842 Joules
How many Kilojoules are obtained from burning 982.6 g of ethanol?

Answer 1

`189kJ`

Step-by-step explanation:

Hello!

In this case, since one mole of ethanol release 8,842 J per 1 mole of ethanol, we can write:

`(8,842J)/(1molC_2H_6H)`

Thus, since we need the energy released by 982.6 g of ethanol, we compute the moles in such mass of fuel:

`n=982.6g(1mol)/(46.08g) =21.3mol`

Therefore, the result is:

`(8,842J)/(1mol)*21.3mol=188,545J`

Which in kJ is:

`189kJ`

Best regards!