Please help! Don't forget to add your answer in kJ

The answer to your question is given below.

Explanation:

The equation for the reaction is given below:

2H2O —> 2H2 + O2... ΔH = –572KJ

A. The reaction is exothermic since the enthalphy change, ΔH has a negative sign.

B. Since the enthalphy change, ΔH has a negative sign for the reaction, It means heat has be released to the surroundings. Therfore, 86.4g will also release heat.

C. We'll begin by calculating the mass of H2O that reacted from the balanced equation.

Molar mass of H2O = (2x1) + 16 = 18g/mol

Mass of H2O from the balanced equation = 2 x 18 = 36g.

From the balanced equation above:

When 36g of H2O reacted, –572KJ of heat were released.

Therefore, 86.4g of H2O will react to release = (86.4 × –572)/36 = –1372.8KJ of heat.

Therefore, –1372.8KJ of heat is released.

14 days is the half-life of phosphorus-32