Question

I am given a series of steps of a a reaction, from which I need to find the overall reaction
and overall enthalpy change under standard conditions
1) the steps are not balanced. Do I need to balance the steps in order to find enthalpy change for each individual reaction?

2) what is the reaction formula for methane gas from solid carbon and Hydrogen gas and

Answer 1

Yes, you HAVE to balance the reactions. Then you line them up and arrange them so everything cancels out, leaving only the reaction you are looking for. For this, you may have to multiply a reaction or two. So
A+3B -> C
2C+D -> E
2E+F->G+B
If you are looking to cancel E, then you need to multiply the second equation by 2, so the 2E cancels out.

Answer 2

thank you