A solution is made by diluting 25.0 mL of concentrated HCl(37 % by weight; density =1.19 g / m

step 1 In answering this question, we have to recall that the pH is calculated as negative low, the con

A solution is made by diluting 25.0 mL of concentrated...

A solution is made by diluting $25.0 \mathrm{~mL}$ of concentrated $\mathrm{HCl}(37 \%$ by weight; density $=1.19 \mathrm{~g} / \mathrm{mL})$ to exactly $500 \mathrm{~mL}$. Calculate the $\mathrm{pH}$ of the resulting solution.

Key Concepts

Weight Percentage

Weight percentage is a concentration metric that expresses the mass of a solute divided by the total mass of the solution, multiplied by 100. It is used to indicate how much of the acid is present in a concentrated solution and is essential for determining the actual amount of acid available before dilution.

Density

Density is the mass per unit volume of a substance and is crucial for converting between the volume of the solution and its mass. In the context of preparing solutions, density allows one to determine the total mass of a given volume of the concentrated acid solution, which is then used with weight percentage to calculate the mass of the acid present.

Molarity Calculation

Molarity is a measure of the concentration of a solution expressed as the number of moles of solute per liter of solution. Calculating molarity involves determining the number of moles of the acid using its mass (derived from the weight percentage and density) and then dividing by the volume of the solution after dilution.

Dilution Principles

Dilution involves reducing the concentration of a solution by adding more solvent. The total moles of solute remain constant while the volume increases. This principle is used to calculate the final concentration of the acid after it has been diluted to a specified final volume.

pH Calculation

pH is a measure of the acidity or basicity of a solution, defined as the negative logarithm (base 10) of the hydrogen ion concentration. For a strong acid like HCl, which completely dissociates in water, the concentration of the acid directly provides the concentration of hydrogen ions, allowing the straightforward calculation of pH.

Transcript

Please give Ace some feedback