From the reaction below, calculate the free energy of formation for C3H6(g) at 25°C, if ΔGfo(CH4(g)) is -50.790 kJ/mol.
3CH4(g) ↔ C3H6(g) + 3H2(g) ΔGo = 215.302 kJ/mol
i've tried doing final-initial, and products minus reactants but i'm not getting the right answer
Instead of me flying in the dark why don't you post your work on the products-reactants you've tried and let me find the error in your work.
3(2.02) + 3(12.01) + 6.06 = 48.15 mol products
3(12.01)+ 3(4.04)=48.15 mol reactants
Prod-React=0
Where in the world are you getting your numbers. I don't see 2.02 or 12.01 in the problem. Wait, I suspect you are using molar mass H2 and molar mass C and molar mass. That isn't what the problem is all about.
dGrxn = (n*dGproducts) - (n*dGreactants)
They give you dGrxn = 215.302 so
215.302 = (1*dGC3H6 + 1*dGH2) - (3*dGCH4)
dGC3H6 is what we solve for.
dGH2 = 0 (dG for all elements is zero)
dGCH4 they give you as -50.790
215.302 = (1*dGC3H6 + 0) -(3*-50.790)
Solve for dGC3H6
Hope this helps.
To calculate the free energy of formation for C3H6(g) at 25°C, we'll use the equation:
ΔGfo(C3H6(g)) = Σ(nΔGfo(products)) - Σ(mΔGfo(reactants))
Here's how to calculate it step by step:
1. First, we need to determine the coefficients (n and m) for the products and reactants in the reaction equation.
The balanced equation for the reaction is:
3CH4(g) ↔ C3H6(g) + 3H2(g)
From this equation, we can see that:
n = 1 (coefficient of C3H6(g))
m = 3 (coefficients of CH4(g))
2. Next, we need to determine the free energy values for the products and reactants.
Given ΔGfo(CH4(g)) = -50.790 kJ/mol
And ΔGo = 215.302 kJ/mol (this is the standard free energy change for the reaction as written)
3. Now we can substitute the values into the equation and calculate the free energy of formation for C3H6(g):
ΔGfo(C3H6(g)) = (nΔGfo(products)) - (mΔGfo(reactants))
= (1 * ΔGfo(C3H6(g))) - (3 * ΔGfo(CH4(g)))
= (1 * ΔGo(products)) - (3 * ΔGfo(CH4(g)))
= ΔGo - 3ΔGfo(CH4(g))
= 215.302 kJ/mol - 3*(-50.790 kJ/mol)
= 215.302 kJ/mol + 152.370 kJ/mol
= 367.672 kJ/mol
So, the free energy of formation for C3H6(g) at 25°C is 367.672 kJ/mol.