Ammonia has . For a 0.0010 M aqueous solution of NH , a student assumes the…
CHEMISTRY · Single correct · A Level · Chemistry · Acids and bases · Acids and bases
Problem
Ammonia has Kb=1.8×10−5. For a 0.0010 M aqueous solution of NH3, a student assumes the equilibrium concentration of NH3 equals 0.0010 M when calculating pH. Which choice best describes both the validity of the assumption and the direction of the resulting pH error?
(a) Assumption valid; calculated pH will be too low
(b) Assumption valid; calculated pH will be too high
(c) Assumption invalid; calculated pH will be too high
(d) Assumption invalid; calculated pH will be too low