How many moles are there in 34.5 g of sodium? (Atomic mass of Na = 23 u)
Molar mass of sodium(Na) = 23g
Given Mass of the sodium = 34.5g
As we know that, Number of moles= mass of an element/molar mass of an element
Hence Number of moles = 34.5/23 = 1.5 moles.