) A chemical reaction requires 31.39 kJ. How many kilocalories does this correspond to?
To convert from kilojoules to kilocalories, you can use the conversion factor 1 kJ = 0.239 kcal.
Therefore, 31.39 kJ * 0.239 kcal/kJ = 7.49 kcal
So, 31.39 kJ corresponds to 7.49 kilocalories.