NEET levelSingle correct optionDifficulty 1 of 3ia175
What is the approximate pH of a solution that is 0.1M in NaOH and 0.1M in NHX3 (Kb=1.8×10−5)?
A12.70
B11.13
C13.00
D12.00
Answer: C
The strong base fixes [OHX−]≈0.1M, because ammonia's ionisation is suppressed (it adds only about 1.8×10−5M). So pOH=1 and pH=13.00. The value 11.13 is for ammonia alone.