how much heat will be released if 2.55 g of hydrogen peroxide H202 decomposes in a bombardler beetle to produce steam spray?

Question

2H2O2 -> 2H2O + O2

DeltaH= -190.0kj

Answer 1

2H₂O₂ ==> 2H₂O + O₂ ... balanced equation

2.55 g H2O2 x 1 mol H2O2/34.0 g = 0.075 moles H2O2

0.075 moles H2O2 x -190.0 kJ/2 moles H2O2 = -7.125 kJ = 7.13 kJ of heat will be released (- sign)