The mass of one mole ${}^{12}\text{C}$ atom in grams is :

One mole of oxygen atom weighs 16 grams, what will be the mass (in grams) of 0.4 moles of oxygen atoms?

One mole of oxygen atom weighs 16 grams, what will be the mass (in grams) of 0.4 moles of oxygen atoms?

Is molecular mass , atomic mass , gram molecular mass, gram atomic mass one mole.

(Like, is 12amu C one mole particles)