Question

A chemist dissolves of pure hydroiodic acid in enough water to make up of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.

Answer 1

To calculate the pH of a hydroiodic acid solution, you need to determine the initial concentration of hydronium ions. For a 0.100 M solution of hydroiodic acid, the pH is 1.00.

Step-by-step explanation:

The concentration of hydronium ion in a solution of hydroiodic acid can be expressed as the pH of the solution. To calculate the pH of the solution, you need to determine the initial concentration of hydronium ions. Since hydroiodic acid is a strong acid, you can assume that all of it dissociates. If you dissolve 0.100 mol of hydroiodic acid in enough water to make up 1.00 L of solution, the initial concentration of hydronium ions is 0.100 M. The pH of the solution can be calculated using the formula pH = -log[H3O+]. Therefore, the pH of the solution is -log(0.100) = 1.00.

Answer 2

1.76

Step-by-step explanation:

There is some info missing. I think this is the original question.

A chemist dissolves 660.mg of pure hydroiodic acid in enough water to make up 300.mL of solution. Calculate the pH of the solution. Be sure your answer has the correct number of significant digits.

Step 1: Calculate the molarity of HI(aq)

M = mass of solute / molar mass of solute × liters of solution

M = 0.660 g / 127.91 g/mol × 0.300 L

M = 0.0172 M

Step 2: Write the acid dissociation reaction

HI(aq) ⇄ H⁺(aq) + I⁻(aq)

HI is a strong acid, so [H⁺] = 0.0172 M

Step 3: Calculate the pH

pH = -log [H⁺]

pH = -log 0.0172

pH = 1.76