When 10.00g of phosphorus is burned in O2(g) to form P4O10(s), enough heat is generated to raise the temperature of 2990g of water from 18.0 ∘C to 38.0 ∘C.
Calculate the heat of formation of P4O10(s) under these conditions.
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Estimate the mass of water that must evaporate from the skin to cool the body by 0.45∘C. Assume a body mass of 85kg and assume that the specific heat capacity of the body is 4.0 J/g⋅∘C.
Evaporating sweat cools the body because evaporation is an endothermic process:
H2O(l)→H2O(g)ΔH∘rxn=+44.01kJ
I am basically at a lost on how to start both of these problems. Any help is appreciated..