ANSWER
Step-by-step explanation
Ammonia (NH3) is a base that does not contain hydroxyl ion but dissolved in water to produce ammonium ion and hydroxyl ion.
Recall, that pH scale is one of the tool used in determining a strong base and a weak base
The pH of ammonia is 11 and this make ammonia (NH3) to fall under the category of weak base
Therefore, ammonia is a weak base