Question: how many moles in 64 grams of ch4?
Answer: of moles of methane = Given mass/molar mass = 64/16 = 4. So, there are 4 moles of methane or 4* 6.022 * 10^23 molecules of methane [ one mole has weight as molecular weight in gm] or 10 * 4 * 6.022 *10^23 e in 64 gm of methane [as each molecule has 10e].