Question

A typical solution used in general chemistry laboratories is 3.0 M $\mathrm{HCI}$ . Describe, in detail, the composition of 2.0 L of a 3.0-M $\mathrm{HCI}$ solution. How would 2.0 L of a 3.0-M ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$solution differ from the same quantity of the $\mathrm{HCI}$ solution?

Short answer

2.0 L of a3.0 M${\text{HC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}$ solution differs from the same quantity of $\text{HCl}$ solution by the mass of solute present in the same quantity of solution. In 2.0 L of 3.0 M${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$solution, 360 g of solute is present. In contrast, a 2.0 L solution of 3.0 M$\mathrm{HCL}$has 219 g of solute.

Step-by-step solution

Definition

A solution's molarity is a concept that refers to the amount of solutecontained in one litre of the solution. It may be stated mathematically as follows:

Molarity$=\frac{\mathrm{moles}\mathrm{of}\mathrm{solute}}{\mathrm{volume}\mathrm{of}\mathrm{solution}\mathrm{in}\mathrm{liter}}$

Explanation of the composition of 2.0 L of a 3.0M HCI solution.

$\begin{array}{c}\text{MassofHCL=Molarity}\times \text{molarmassofHCl}\times \text{Volumeofsolution}\\ \text{=3.0}\raisebox{1ex}{$\text{mol}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{L}$}\right.\times 36.5\raisebox{1ex}{$\text{g}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{L}$}\right.\mathrm{mol}\times 2.0\text{L}\\ \mathrm{Mass}\mathrm{of}\mathrm{HCL}=219\text{g}\end{array}$

$\begin{array}{c}{\text{MassofHC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}\text{=Molarity}\times {\text{molarmassofHC}}_{\text{2}}{\text{H}}_{\text{3}}{\text{O}}_{\text{2}}\times \text{Volumeofsolution}\\ \text{=3.0}\raisebox{1ex}{$\text{mol}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{L}$}\right.\times 60\raisebox{1ex}{$\text{g}$}\!\left/ \!\raisebox{-1ex}{$\mathrm{L}$}\right.\mathrm{mol}\times 2.0\text{L}\\ \mathrm{Mass}\mathrm{of}{\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2=360\text{g}\end{array}$

As a result, the composition of a 2.0 L of 3.0 M ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$ solution is 360 g of ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$ in the 2.0L solution.

Bythe mass of solute present in the same quantity of solution, 2.0 L of a 3.0 M ${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$solution differs from the same quantity of $\mathrm{HCL}$ solution. 360 g of solute is present in 2.0 L of a 3.0 M${\mathrm{HC}}_2{\mathrm{H}}_3{\mathrm{O}}_2$ solution. A 2.0 L solution of 3.0 M $\mathrm{HCL}$, on the other hand, has 219 g of solute.