For nitrous acid, HNO₂, K_a = 4.0 × 10^-4. Calculate the pH of 0.33 M HNO₂.

Name: For nitrous acid, HNO 2 , K a = 4.0 × 10 -4 . Calculate the pH of 0.33 M HNO 2 .
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Quizplus · Accepted Answer

The pH is calculated using the formula pH = -log[H+]. For a weak acid like HNO2, [H+] can be approximated using the formula [H+] = √(Ka × [HNO2]). Substituting the given values, [H+] = √(4.0 × 10^-4 × 0.33) = √(1.32 × 10^-4) ≈ 0.0115. Thus, pH = -log(0.0115) ≈ 1.94.

For Nitrous Acid, HNO2, Ka = 4

For Nitrous Acid, HNO₂, K_a = 4