explain how the mass of a substance relates to the number of moles?

Answer 1

if you look on periodic table 1.008 g of hydrogen contains 1 mole of hydrogen. (took chemistry long ago)

Answer 2

Mass = No. of Moles x Mass of one mole

a mole of a molecular substance (6.022 × 1023 molecules) is the amount of the substance whose mass (in grams) is equal to its molecular weight.
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