Question

Which one of the following statements best describes a solution with a pH of 3?

Answer 1

Statement D is the correct option as the solution will have pH of 3. It has an H3O+ ion concentration of 1 × $10^{-3}$ mol/L and is acidic.

Explanation:

It is given in question that solution must have pH of 3. The value if being less than 7 shows that solution is acidic. The pH value of 3 indicates that given solution is highly acidic and has strong acid. Strong acid gets fully dissociated into $H_{3}$$O^{+}$ ions.

pH of the solution is calculated as:

pH = -log10[$H_{3}$$O^{+}$]

the concentration or molarity of the hydronium ion is given as moles/litre

concentration of hydronium ion in the solution is 1 X $10^{-3}$ moles/litre

putting the values in the equation:

pH = - log10( 1 X $10^{-3}$)

pH = 3 (acidic)

Thus it can be concluded that D option is the right answer.