Question

Calculate the weight of 0.1 moles of Na_{​​​​​2}​CO₃ ?

Answer 1

One mole of Na_{​​​​​2}​CO₃ weighs 106 gms
therefore 0.1 mole weighs 10.6 gms
Atom's weight = no of moles x molecular mass of atom
no of moles = given mass of atom / molecular mass of atom

W= 0.1 X 106 = 10.6