A question on chemistry

Question

Hydrogen peroxide can decompose to water and oxygen

    

   2 H2O2(l)  2 H2O(l) + O2(g)                               H = -196 kJ

 

What will the the amount of heat be released when 15.5 g of H2O2(l) decomposes at a constant pressure.

Answer 1

15.5 g H2O2 x 1 mol H2O2 / 34 g = 0.456 moles H2O2

Heat produced from 2 moles H2O2 = -196 kJ

Therefore...

0.456 moles H2O2 x -196 kJ/ 2 mol H2O2 = -44.7 kJ