How many moles of (NH4) 2S are there in 150 g of (NH4) 2S?

The answer

the number of moles can be found easily by using formula of molar mass

Molar mass = mass (g) / number of moles (mol)

from this, we can get number of

number of moles (mol) = mass (g) / Molar mass

the mass molar of (NH4) 2S:

M ((NH4) 2S) = (14 + 4x1) x 2 + 32 = 36+32 = 48 g / mol

number of moles (mol) = 150 g / 48 = 3.12 moles