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In: Chemistry

An experiment procedure starts with 625.0 mL of a 9.10 M hydrocyanic acid (HCN(aq)) solution. During...

An experiment procedure starts with 625.0 mL of a 9.10 M hydrocyanic acid (HCN(aq)) solution. During the course of the experiment, the volume of the this acid solution is increased by 1.457 L by the addition of water solvent as part of the outcome. Based on this information, what would be the altered molar concentration of the aqueous HCN solution?

Solutions

Expert Solution

Given data: V = 625 ml = 0.625 L, Molarity = 9.10 M

Moles of HCN = Molarity × Volume

= 9.1 × 0.625 = 5.6875 moles.

Now 1.457 L of water is addedto the HCN. Then

V = 0.625 + 1.457 = 2.082 L, Mol of HCN = 5.6875 moles

Concentration of HCN = Moles of HCN in solution / Volume of Solution

= 5.6875 moles / 2.082 L = 2.73 M.

Hence the final concentration of aqueous HCN solution is 2.73 M.


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