What is the molarity of a solution in which 7.1 g of sodium sulfate is dissolved in enough water to make 100. mL of solution?

0.50 M

Explanation:

Given data

Step 1: Calculate the moles of the solute

The molar mass of sodium sulfate is 142.04 g/mol. The moles corresponding to 7.1 grams of sodium sulfate are:

Step 2: Convert the volume of solution to liters

We will use the relation 1 L = 1000 mL.

Step 3: Calculate the molarity of the solution

0.5 M

Explanation:

Hello,

In this case, since sodium sulfate molar mass is 142.04  g/mol we first need to compute the moles in 7.1 g as shown below:

Then, since 100 mL are 0.1 L the molarity turns out:

Regards.