How many hydrogen atoms are there in 2.0 moles of ch4?

There are 6.02 x 10^23 molecules in one mole of methane (CH4) since you have two moles we double this by 2.
2(6.02 x 10^23) this is the number of methane molecules.
Since there are four hydrogen atoms for every one Methane molecule multiply the perilous answer by four
4x (2x (6.02 x 10 ^ 23)
= 4.816 x 10 ^24