Question

calculate the no. of moles in 7 g of Na

Answer 1

no. of moles = given mass /molar mas
molar mass of Na= 23 gm
given mass= 7 gm
no. of moles= 7/23 mol

Answer 2

no. of moes = given mass / molar mass
=7/23
=0.30 moles (approx.)