 The problem reads determine the change in the free energy of the reaction at standard state for the following reaction C2H4 gas plus H2O liquid goes to C2H5 OH liquid So we're going to be looking for Delta G theta Rxn So that's standard state right and we're going to use Hess's formula That says that Delta G theta of the reaction this means in standard state Is the sum of the changes in the free energy? For the formation of the products minus the sum the change in the in the free energy of the formation of the reactants Now we get these from tables So let's find the first one which would be Delta G theta F of C2H4 so Delta G theta F of C2H4 at gas Let's find our table. So here's our table. Here's what we're looking for Delta GF theta and C2H4 is right here gas good and we go over to there sixty eight point two kilo Joules per mole Sixty eight point two kilo Joules per mole Now we want Delta G theta of formation of H2O Liquid back to our table. We need to scroll down. So go we down down down down down there it comes H2O liquid minus two thirty seven point one kilo Joules per mole Minus two thirty seven point one kilo Joules per mole and the last one is Delta G theta of formation of C2H5OH liquid Our table and we can see it's here C2H5OH liquid minus one seventy eight point eight minus one seventy eight point eight kilo Joules per mole So now we substitute into our formula. So Delta G theta of the reaction is Equal to products. This is product so minus one seventy eight point eight minus Parenthesis what do we have for reactant sixty eight point two plus this is a sum and then we have minus two thirty seven point one So I'll get a calculator out to calculate this So minus one seventy eight point eight minus Parenthesis sixty eight point two Plus and then minus two thirty seven point one and the parentheses enter minus nine point nine so Minus nine point nine everything was kilo Joules per mole so this is our answer and because Delta G theta our Xn is less than zero. This is a spontaneous reaction