Question

100.0 mL of a 0.695 M solution of KBr is diluted to 500.0 mL. What is the new concentration of the solution?

Answer 1

Answer:

0.116 M

Explanation:

(Step 1)

Calculate the amount of moles using the molarity ratio.

100.0 mL / 1,000 = 0.1000 L

Molarity = moles / volume

0.695 M = moles / 0.1000 L

0.0695 = moles

(Step 2)

Calculate the new molarity using the moles and new volume.

500.0 mL / 1,000 = 0.5000 L

Molarity = moles / volume

Molarity = 0.0695 moles / (0.1000 L + 0.5000 L)

Molarity = 0.0695 moles / (0.6000 L)

Molarity = 0.116 M