Answer
(a) $pH \approx 7$
(b) $pH \lt 7$
(c) $pH \approx 7$
(d) $pH \lt 7$
Work Step by Step
(a) Analyze the conjugate pairs of the anions:
$KOH$ is a strong base and $HBr$ is a strong acid.
Therefore, this salt is going to form a nearly neutral aqueous solution: $pH \approx 7$
(b) Analyze the conjugate pairs of the anions:
$Al(OH)_3$ is a weak base and $HNO_3$ a strong acid.
Therefore, a solution with this salt is going to be acidic. $pH \lt 7$
(c) Analyze the conjugate pairs of the anions:
$Ba(OH)_2$ is a strong base and $HCl$ is a strong acid.
Therefore, a $BaCl_2$ solution is nearly neutral $pH \approx 7$
(d) Analyze the conjugate pairs of the anions:
$Bi(OH)_3$ is a weak base and $HNO_3$ a strong acid.
Therefore, a $Bi(NO_3)_3$ solution is going to be acidic: $pH \lt 7$
