Answer: The mass of potassium superoxide required is 142.2 grams
Step-by-step explanation:
The chemical equation for the reaction of potassium superoxide with water follows:

Number of moles of potassium superoxide reacted = 2 moles for given amount of heat released
To calculate the mass for given number of moles, we use the equation:

Molar mass of potassium superoxide = 71.1 g/mol
Moles of potassium superoxide = 2 moles
Putting values in above equation, we get:

Hence, the mass of potassium superoxide required is 142.2 grams