Question

A solution is prepared by dissolving 30. g of KNO3 into 100. mL of total solution. What is the molarity of this solution?

Answer 1

3.0 M

Step-by-step explanation:

The molarity formula is M = n/v

where M is the molarity, n is the number of moles, and v is the volume in litres.

step 1: convert the grams of KNo3 to moles. To convert grams to moles, divide by the molar mass.

(30 g divided by 101.103 g/mol) = 0.296 moles

step 2: convert the volumes to Litres. 100 mL is 0.1 L

step 3: apply the formula. Molarity = (0.296 mol / 0.1 L) = 2.96 mol/L

We will round our answer to 3.0 M