Question

Liquid hydrogen peroxide, an oxidizing agent in many rocket fuel mixtures, releases oxygen gas on decomposition.

2 H2O2(l) 2 H2O(l) + O2(g) Hrxn = -196.1 kJ
How much heat is released when 765 kg H2O2 decomposes?

Answer 1

4.3 x 10⁶ kJ are released

Step-by-step explanation:

From the balanced chemical equation we know that when 2 moles of hydrogen peroxide decompose, 191 kJ of heat are released. So what we need to calculate is the number of moles the 765 kg of H2O2 represent and calculate the heat released.

Molar Mass H2O2 = 34.01 g/mol

Mass H2O2 = 765 Kg x 1000 g/Kg = 765000 g

moles H2O2 = 1 Mol / 34.01 g x 765000 grams = 22.5 Mol

(-196.1 kJ/ 2 mol H2O2 ) x 22.5 mol H2O2 = -4.3 x 10⁶ kJ