Answer:
Steam because steam pushes out and ice stays dormant.
Explanation:
Answer: A. -396 kJ
Explanation:
The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.

Reversing the reaction, changes the sign of 

On multiplying the reaction by 2, enthalpy gets multiplied by 2:

Thus the enthalpy change for the reaction
is -396 kJ.