Question

If a student has 450mL of a 3.2M HCl solution and wants the molarity to be 0.85M, what volume do they need to dilute it to?

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Answer 1

1.694 L

Step-by-step explanation:

First, solve for the number of moles of HCl in a 450-ml 3.2M solution:

# of mol HCl = (3.2 mol HCl/L)(0.450 L)

= 1.44 mol HCl

The molarity M is given by

M = (# of moles)/(volume in L)

Solving for the volume,

V = (# of moles)/M

= (1.44 mol HCl)/(0.85M)

= 1.694 L

Therefore, the 3.2M HCl solution must be diluted until its volume becomes 1.694 L.