23.1 G Of HCI (a Strong Acid) Is Added To Water To Make 1250 ML Of Solution.

[H₃O⁺] = 0.0507 M

pH = 1.29

Explanation:

23.1 g of HCI (a strong acid) is added to water to make 1250 mL of solution. Calculate [H₃O⁺] and pH of the solution.

Step 1: Given data

Step 2: Calculate the concentration of HCl

We will use the following expression.

[HCl] = mass HCl / molar mass HCl × liters of solution

[HCl] = 2.31 g / 36.46 g/mol × 1.250 L

[HCl] = 0.0507 M

Step 3: Calculate the concentration of H₃O⁺

HCl is a strong acid according to the following equation.

HCl(aq) + H₂O(l) ⇒ H₃O⁺(aq) + Cl⁻(aq)

The molar ratio of HCl to H₃O⁺ is 1:1. Then, [H₃O⁺] = 0.0507 M.

Step 4: Calculate the pH of the solution

We will use the following expression.

pH = -log [H₃O⁺]

pH = -log 0.0507

pH = 1.29