Question

A chemist prepares a solution of potassium dichromate by measuring out of potassium dichromate into a volumetric flask and filling the flask to the mark with water. Calculate the concentration in of the chemist's potassium dichromate solution. Be sure your answer has the correct number of significant digits.

Answer 1

Answer:

0.297 mol/L

Explanation:

A chemist prepares a solution of potassium dichromate by measuring out 13.1 g of potassium dichromate into a 150 mL volumetric flask and filling the flask to the mark with water. Calculate the concentration in mol/L of the chemist's potassium dichromate solution. Be sure your answer has the correct number of significant digits.

Step 1: Calculate the moles corresponding to 13.1 g of potassium dichromate

The molar mass of potassium dichromate is 294.19 g/mol.

13.1 g × (1 mol/294.19 g) = 0.0445 mol

Step 2: Convert the volume of solution to L

We will use the relationship 1 L = 1000 mL.

150 mL × (1 L/1000 mL) = 0.150 L

Step 3: Calculate the concentration of the solution in mol/L

C = 0.0445 mol/0.150 L = 0.297 mol/L