How many grams are presented in a 7.4 moles sample of H2O?

130g

Explanation:

For every mole of a substance, there is a molar mass that coincides with the masses on the periodic table. For one mole of H2O, you would add the molar masses of the two hydrogen atoms and the oxygen atom to get 18.016g. You would then take this molar mass and multiple it by the amount of moles present (7.4) to get 133.3184g

From here, you would round to the significant figures to get 130g

i'm assuming that the correct answer is indeed the first one/ "a"..