Question

A 25.00 mL aliquot of concentrated hydrochloric acid (11.7M) is added to 175.00 mL of 3.25M hydrochloric acid. Determine the number of moles of hydrochloric acid from 175.00 mL of 3.25 M hydrochloric acid solution.

Answer 1

Answer:

The number of moles of hydrochloric acid are 0.861

Explanation:

In first solution, the [HCl] is 11.7 M, which it means that 11.7 moles are present in 1 liter.

So we took 25 mL and we have to know how many moles, do we have now.

1000 mL ____ 11.7 moles

25 mL _____ (25 . 11.7)/1000 = 0.2925 moles

This are the moles, we add to the solution where the [HCl] is 3.25 M

In 1000 mL __ we have __ 3.25moles

175 mL ____ we have __ (175 . 3.25)/1000 = 0.56875 moles

Total moles: 0.2925 + 0.56875 = 0.861 moles