Question

Explosive is HMX

The prospective buyer wants to know the actual explosive power of your substance. Explosive power is defined as the heat of explosion (kJ/kg) x the volume of gases (L/g) produced (at final temperature). Calculate the explosive power of your substance. Use the volume of your gas produced after heating by "heat of explosion".  

Answer 1

HMX is an explosive with chemical formula C₄H₈N₈O₈

On explosion C₄H₈N₈O₈ ---------> 4CO + 4H₂O + 4N₂   

Water is converted to steam and it is considered as gaseous product.

So 1 mole of HMX produce 12 moles of gaseous molecules on explosion.

Each mole of HMX produce 22.4 dm³

12 moles of HMX ---> 268.8 dm³ (12 x 22.4)

Molar mass of HMX = 296.155 g/mol

Each gram of HMX ----> 268.8 dm³/296.155 g = 0.9076 = 0.908 dm³/g

Volume of gas produced, V= 0.908 dm³/g = 0.908 l/g (1 dm³ = 1l)

Heat of explosion,Q = 5010 kJ/g

1 g ----> 5010 kJ

1000 g ---> 5010 x 10³ kJ/Kg

Explosive power = Q x V = 5010 x 10³ kJ/Kg x 0.908 l/g = 454.908 J l/g²