What is the enthalpy for the following reaction?

Question

C2H4+H2O--->C2H5OH

Answer 1

Look up delta H^o_f for products and reactants, then
delta Hrxn = (delta H sum products)-(delta H sum reactants)

Answer 2

formation enthalpy of ethane -> –83.8 kJ/mol

formation enthalpy of water -> −291.83 kJ/mol

formation enthalpy of ethanol -> –277.7 kJ/mol

I got 97.93 and got it wrong I only have one try left. I don't know whats wrong.

Answer 3

What phases are these reagents in? It makes a difference if they are in gas or liquid phase. The delta H is considerably different (although the differences may not be different).