I need to know how to figure this out, step by step... Don't assume I know anything.. Break it down for me like I'm a 5 year old... I'm really horrible at figuring out where to even begin... what steps to use.. etc.. Thank you!!

Question

CO2(g)+4H2(g)→CH4(g)+2H2O(g)
How many moles of methane are produced when 59.6moles of carbon dioxide gas react with excess hydrogen gas?
Express your answer with the appropriate units. For example, write the unit moles as mol.

How many moles of hydrogen gas would be needed to react with excess carbon dioxide to produce 19.1moles of water vapor?

Answer 1

This is no different than those problems we've been doing. You can convert any mole in an equation to any mole of something else in the same equation just by using the coefficients in the balanced equation
CO2(g)+4H2(g)→CH4(g)+2H2O(g)

Step 1. You have the balanced equation.
Step 2. Convert what you have to mols but your problem starts with mols so that's already done.
Step 3. The conversion step using the coefficients in the balanced equation.
59.6 mols CO2 x (1 mol CH4/1 mol CO2) = 59.6 mols x 1/1 = 59.6 mols CH4.

You always take the mols of what you have and multiply by the conversion factor (made up of the coefficients in the balanced equation) to convert mols of what you have to mols of what you want.
19.1 mols H2O x (4 mols H2/2 mols H2O) = 19.1 x 4/2 = 19.1 x 2 = 38.2 mols H2 gas produced.