Question

Potassium superoxide is a yellow paramagnetic solid that reacts with water according to the following balanced equation. Calculate the mass of potassium superoxide required to produce 2405 J of heat.

Answer 1

Answer: The mass of potassium superoxide required is 142.2 grams

Explanation:

The chemical equation for the reaction of potassium superoxide with water follows:

$2KO_2+H_2O\rightarrow KOH+KHO_2+O_2;\Delta H=2405J$

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:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of potassium superoxide = 71.1 g/mol

Moles of potassium superoxide = 2 moles

Putting values in above equation, we get:

$2mol=\frac{\text{Mass of potassium superoxide}}{71.1g/mol}\\\\\text{Mass of potassium superoxide}=(2mol\times 71.1g/mol)=142.2g$

Hence, the mass of potassium superoxide required is 142.2 grams