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Concentrated HCl is 12.1 Molar. If I want to prepare 2.00 L of 6.00 M solution how many mL's of concentrate do I need to dissolve?

User Toan NC
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Dilutions:

When a solution is diluted, the total number of moles of solute (n), does not change. Only the totel solution volume changes. As n=cV (molarity formula, where n = moles, c = concentration, V = volume), then the value of cV is a constant when diluting solutions. This can be expressed by the ratio:

c₁V₁ = c₂V₂, where subscripts 1 and 2 represent the concentrated and dilute solutions.

To prepare an 2.00 L aqueous solution of HCl (hydrochloric acid) of concentration 6.00 M from 12.1 M, we can use the dilution ratio:

C₁V₁ = C₂V₂.

Hence: 12.1×V₁ = 6.00×2.00

V₁ = 0.9917 L

therefore, the initial volume, the volume of HCl we start with, is 0.9917 L, or 991.7 mL

User Rizerphe
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