Question

2. (2 pts) How would you prepare 1.5 liters of 2 M KCI (MW=74.55 g/mol)

Answer 1

Answer:

Dissolve 226 g of KCl in enough water to make 1.5 L of solution

Explanation:

1. Calculate the moles of KCl needed

$n = \text{1.5 L} \times \dfrac{\text{2 mol}}{\text{1 L}}= \text{3.0 mol}$

2. Calculate the mass of KCl

$m = \text{3.0 mol} \times \dfrac{\text{74.55 g}}{\text{1 mol}}= \text{224 g}$

3. Prepare the solution

• Measure out 224 g of KCl.
• Dissolve the KCl in a few hundred millilitres of distilled water.
• Add enough water to make 1.5 L of solution. Mix thoroughly to get a uniform solution.