How many atoms are in 1.27 mol of pure aluminum?

Answer 1

Avogadro's number (6.022 x 10²³) tells you how many items are in a mole so that means there are 6.022 x 10²³ atoms in 1 mole of Al

So if you have 1.27 moles, then there is (1.27)(6.022 x 10²³) = 7.65 x 10²³ atoms of Al in the 1.29 moles of Al.