Question

5. Calculate the molarity of a solution made from dissolving 80.Og of lithium

chloride (LiCl) in 800.OmL of solution.

Answer 1

• M = 2.36 mol/liter

Step-by-step explanation:

1. Data:

a) M = ?

b) m = 80.0 g Li Cl

c) V = 800 ml solution

2. Principles and formulae:

Molarity is the unit of concentration that expresses moles of solute per liter of solution:

• M = moles of solute / volume of solution in liters

The number of moles, n, of a compound may be calcualted from its molar mass:

• n = mass in grams / molar mass

3. Solution:

i) Molar mass of LiCl = 42.394 g/mol

ii) Number of moles of solute, LiCl = 80.0 g / 42.394 g/mol = 1.887 mol

iii) Volume of solution = 800.0 ml × 1 liter / 1,000 ml = 0.8000 liter

iv) M = 1.887 mol / 0.8000 liter = 2.36 M ← answer