High School

What is the molarity of a solution made by dissolving 39.4 g of lithium chloride in enough water to make 1.59 L of solution?

[tex]\[ \text{Molar mass of } LiCl = 42.39 \, \text{g/mol} \][/tex]

Answer :

To determine the molarity of a solution, we need to follow these steps:

1. Find the number of moles of [tex]\( \text{LiCl} \)[/tex] dissolved in the solution.
2. Determine the volume of the solution in liters.
3. Calculate the molarity using the relationship:
[tex]\[
\text{Molarity} = \frac{\text{Number of moles}}{\text{Volume of solution in liters}}
\][/tex]

### Step 1: Calculate the number of moles of [tex]\( \text{LiCl} \)[/tex]

We are given:
- Mass of [tex]\( \text{LiCl} \)[/tex]: 39.4 grams
- Molar mass of [tex]\( \text{LiCl} \)[/tex]: 42.39 grams per mole

The number of moles is calculated using the formula:
[tex]\[
\text{Number of moles} = \frac{\text{Mass}}{\text{Molar mass}}
\][/tex]

Substituting the given values:
[tex]\[
\text{Number of moles of } \text{LiCl} = \frac{39.4 \text{ grams}}{42.39 \text{ grams per mole}} \approx 0.929 \text{ moles}
\][/tex]

### Step 2: Volume of the solution

We are given:
- Volume of the solution: 1.59 liters

### Step 3: Calculate the molarity

Molarity is calculated using the formula:
[tex]\[
\text{Molarity} = \frac{\text{Number of moles}}{\text{Volume of solution in liters}}
\][/tex]

Substituting the values we have:
[tex]\[
\text{Molarity} = \frac{0.929 \text{ moles}}{1.59 \text{ liters}} \approx 0.585 \text{ M}
\][/tex]

Therefore, the molarity of the solution is approximately [tex]\( 0.585 \)[/tex] M.

Other Questions