pH Chemistry Example 3

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Example 3

medium
What is the pH of a 0.001 M0.001\,\text{M} HCl solution? (HCl is a strong acid.)

Solution

  1. 1
    HCl fully dissociates: [H+]=0.001=1.0×10−3 M[\text{H}^+] = 0.001 = 1.0 \times 10^{-3}\,\text{M}.
  2. 2
    pH=−log⁡(10−3)=3\text{pH} = -\log(10^{-3}) = 3.

Answer

pH=3\text{pH} = 3
For strong acids, the [H+][\text{H}^+] equals the molarity of the acid since it fully dissociates.

About pH

A logarithmic scale ranging from 0 to 14 that quantifies the hydrogen ion concentration [H+][\text{H}^+] in an aqueous solution, where values below 7 indicate acidic.

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More pH Examples

Example 1 easy

Calculate the pH of a solution with [formula].

Example 2 medium

A solution has pH = 9. Calculate [formula] and [formula].

Example 4 medium

Compare a solution with pH 2 and a solution with pH 5. How many times greater is the hydrogen-ion co

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