Answer:
D) KBr(aq)
Step-by-step explanation:
The salt has pH = 7 or is neutral when it is made up of a strong acid and a strong base.
A) NaCN is made up of NaOH and HCN.
NaOH is a strong base but HCN is a weak acid. It will have pH greater than 7.
B) NH₄Br is made up of NH₄OH and HBr.
NH₄OH is a weak base and HBr is a strong acid. It will have pH less than 7.
C) NaCN is made up of NaOH and HCN.
NaOH is a strong base but HCN is a weak acid. It will have pH greater than 7.
D) KBr is made up of KOH and HBr.
KOH is a strong base and also HBr is a strong acid. It will have pH equal to 7.
E) Ca(NO₂)₂ is made up of Ca(OH)₂ and HNO₂.
Ca(OH)₂ is a strong base but HNO₂ is a weak acid. It will have pH greater than 7.