Question

Calculate the number of moles for 60 grams of helium

Answer 1

given mass of He (m) = 60 g 
molar mass of He (M) = 4 g 
so number of moles in 60 g of helium = m /M
n = 60/4 
n = 15 
therefore number of moles in 60 g of He = 15 moles..
i hope it helps............

Answer 2

atomic mass of helium =4g
number of moles in 60 gram of helium=60/4=15 moles



I hope it will help u