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Chemistry · EQUILIBRIUM
हिन्दीFor hydrofluoric acid (\( \text{HF} \)), \( K_a = 3.2 \times 10^{-4} \). Solving the exact equilibrium expression \( K_a = \frac{c\alpha^2}{1-\alpha} \) for a \( 0.02\text{ M} \) solution gives a degree of dissociation \( \alpha = 0.12 \). What is the equilibrium concentration of unionized \( \text{HF} \)?
Correct answer · Option 1
\( 1.76 \times 10^{-2}\text{ M} \)
Explanation
\( [\text{HF}] = c(1 - \alpha) = 0.02(1 - 0.12) = 0.02 \times 0.88 = 0.0176\text{ M} = 1.76 \times 10^{-2}\text{ M} \).
