A chemical reaction release 55.2 kcal. How many kilojoules does this correspond to?

231.0 kJ

Explanation:

Chemical reactions releasing heat energy are exothermic reactions.

The chemical reaction released 55.2 kcal

1 kcal is equivalent to 4.184 kJ

Therefore 55.2 kcal is equivalent to - 4.184 kJ/kcal x 55.2 kcal

the energy in kJ is - 231.0 kJ