Question

How many moles of HCL are in 20 ml sample of .10 M HCL

Answer 1

Answer:

0.002 moles

Explanation:

Concept tested: Molarity

We are given;

• Volume of HCl as 20 ml or 0.02 L
• Molarity of HCl solution as 0.10 M

We are required to calculate the number of moles of HCl

What is molarity?

• Molarity is the concentration of a solution in moles per liter

How is it calculated?

• It calculated by dividing number of moles by volume;
• Molarity = Number of moles ÷ Volume

To calculate the number of moles we rearrange the formula;

Moles = Molarity × Volume

In this case;

Moles of HCl = 0.10 M × 0.02 L

                      = 0.002 moles

Therefore, the number of moles of HCl is 0.002 moles