[trogdor3491]

The question is:

When a corpse decomposes, much of the phosphorus in the body is converted to phosphine PH(3) (or phosphorus trihydride), a colorless gas with a rotting fish odor. Phosphine is a highly reactive molecule that ignites spontaneously in air. Determine deltaH for the combustion of phosphine. The reaction forms tetraphosphorus decaoxide (solid) and water (gas). The enthalpy of formation for phosphine is +5.4 kJ/mol.

Now to determine deltaH for the combustion of phosphine I first need the enthalpy of formation for products and reactants right? So I need the chemical equation which I think is:

4(PH3) + 8(O2) --> P4O10 + 6(H2O)

It gives me phosphine and water's enthalpy of formation which is 5.4 kJ/mol and 241.8 kJ/mol respectively. We also know that O2's enthalpy of formation is 0 but I'm lost on where to find tetraphosphorus decaoxide's (solid) enthalpy of formation.

[Borek]

What happens when you mix P₄O₁₀ with water?