Ethanol is increasingly being used as a fuel for cars.
The standard enthalpy change of formation of carbon dioxide is -393 kJmol.
The standard enthalpy change of formation of water is --286 kJmol.
The standard enthalpy change of formation of ethanol is -277 kJmol.
What is the standard enthalpy change of combustion of ethanol?

=-522.5\,\, kJmol^{-1}

Explanation:

Firstly, we know that 0.36 g of ethanol burned, so we can convert this into a number of moles.

Using a formula triangle to calculate the number of moles of ethanol in a 0.36 gram sample

Secondly, we can use \Delta H=cm\Delta T to calculate the enthalpy change in the experiment described in the question (ie when 0.008 moles of ethanol is burned).

\Delta H=cm\Delta T = 4.18 x 0.2 x 5

= 4.18 kJ

Lastly, we can use the enthalpy change for the experiment in the question to calculate the enthalpy of combustion (ie when one mole of ethanol is burned).

0.008\,\,moles\,\,ethanol =4.18kJ

1\,\,mole\,\,ethanol = \frac{1}{0.008} \times 4.18

=-522.5\,\, kJmol^{-1}

1.solid

2.carbon dioxide

3.helium

it is the most commonly accepted one