A weak acid HA has a Ka of 1.00 × 10-5. If 0.100 mole of the acid is dissolved in one litre of water.The percentage of acid dissociated at equilibrium is closest to

Question

A weak acid HA has a Ka of 1.00 × 10-5. If 0.100 mole of the acid is dissolved in one litre of water.The percentage of acid dissociated at equilibrium is closest to (A) 0.100% (B) 99.0% (C) 1.00% (D) 99.9%

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/3ac8848507b63e92e9a2cd4fb1cedfb3-.png" /> We know that Ka = C alpha 2 or a=√(Ka/c)=√(10-5/10-1)=10-2=0.001=1

Q. A weak acid $H A$ has a $K_{a}$ of $1.00 \times 1 0^{- 5}$ . If $0.100$ mole of the acid is dissolved in one litre of water.The percentage of acid dissociated at equilibrium is closest to

0.100%

99.0%

1.00%

99.9%

We know that $K a = C$ alpha $^{2}$
or $a = \frac{K _{a}}{c} = \frac{1 0 ^{- 5}}{1 0 ^{- 1}} = 1 0^{- 2} = 0.001 = 1$

Q. A weak acid HA has a Ka​ of 1.00×10−5. If 0.100 mole of the acid is dissolved in one litre of water.The percentage of acid dissociated at equilibrium is closest to