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Acids, bases and titration — Question 18

QCAA 2022, Paper 1 · 1 mark

Q18 · 2022 · Paper 1Unclassified1 mark

QUESTION 18

Determine the Kb expression for the weak base shown in the equilibrium equation.

+ -

NH (aq) + H O(l)

NH (aq) + OH (aq) ⇌

3 2

4

[NH ][H O] 3 2

(A) K == b + [NH ] 4

[NH ][H O] 3 2

(B) K == b - [OH ]

+ -

[NH ][OH ] 4

(C) K == b [NH ] 3

+ -

[NH ][OH ] 4

(D) K == b [H O] 2

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