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What is the Ka of a 0.653 m solution of hydrocyanic acid with a ph of 5.47

User Bfieber
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2 Answers

1 vote

Answer:

The answer is actually 1.76x10^-11

Step-by-step explanation:

Fill in the box 1.76 and then -11

User Wscourge
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4.4k points
3 votes

Answer:

1.758 x 10⁻¹¹.

Step-by-step explanation:

∵ pH = - log[H⁺].

∴ 5.47 = -log[H⁺].

log[H⁺] = -5.47.

∴ [H⁺] = 3.388 x 10⁻⁶ M.

∵ [H⁺] = √(Ka.C)

∴ [H⁺]² = Ka.C

∴ Ka = [H⁺]²/C = (3.388 x 10⁻⁶)²(0.653) = 1.758 x 10⁻¹¹.

User Diakosavvasn
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4.5k points