Question

Calculate the mass of 1.25 mol ammonium sulfide, (NH4)2S. *

Answer 1

85g

Step-by-step explanation:

To convert the moles of a substance to grams we need to know the molar mass of the substance. We, as first, must obtain the molar mass of (NH₄)₂S as follows:

There are 2 atoms of N, 8 of H and 1 of S:

N = 2*14g/mol = 28g/mol

H = 8*1g/mol = 8g/mol

S = 1*32g/mol = 32g/mol

Molar mass: 68g/mol

That means 1 mole of (NH₄)₂S has a mass of 68g.

1.25moles have a mass of:

1.25moles * (68g/mol) =

85g