Which of the following compounds would dissolved in water to give a solution whose pH is less than 7?A. AI(NO3)3B. KNO3C. N2OD. NH3

A compound that would dissolve in water to give a solution with a pH less than 7 would be an acid.

Looking at the options:

A. AI(NO3)3 - This is Aluminium nitrate, which is a salt of a strong acid (nitric acid) and a weak base (aluminium hydroxide). When it dissolves in water, it will produce a slightly acidic solution due to the hydrolysis of the Al3+ ion.

B. KNO3 - This is Potassium nitrate, which is a salt of a strong acid (nitric acid) and a strong base (potassium hydroxide). When it dissolves in water, it will not affect the pH of the solution, so the solution will remain neutral.

C. N2O - This is Nitrous oxide, which is a neutral compound and will not affect the pH of the solution.

D. NH3 - This is Ammonia, which is a weak base. When it dissolves in water, it will produce a slightly basic solution.

So, the compound that would dissolve in water to give a solution whose pH is less than 7 is AI(NO3)3.