Question

How many moles of br2(l) (mm = 159.80 g/mol) are in 13.9 ml of liquid bromine? the density of br2(l) is 3.12 g/ml?

Answer 1

Moles = 0.271 mol

Solution:

Step 1: Calculate Mass of Br₂ as;

Density = Mass ÷ Volume

Solving for Mass,

Mass = Density × Volume

Putting values,

Mass = 3.12 g.mL⁻¹ × 13.9 mL

Mass = 43.36 g

Step 2: Calculate Moles of Br₂ as;

Moles = Mass ÷ M.Mass

Putting values,

Moles = 43.36 g ÷ 159.80 g.mol⁻¹

Moles = 0.271 mol