question_answer 1)

Write chemical reactions to show amphoteric nature of water.  

Answer:

Water has the ability to act as an acid as well as a base, e., it behaves as an amphoteric substance. It acts as an acid with \[\text{N}{{\text{H}}_{\text{3}}}\]and a base with\[{{H}_{2}}S\]. \[\underset{Acid}{\mathop{{{H}_{2}}O}}\,+N{{H}_{3}}\underset{{}}{\leftrightarrows}\underset{Acid}{\mathop{NH_{4}^{+}}}\,+\underset{Base}{\mathop{O{{H}^{-}}}}\,\] \[\underset{Base}{\mathop{{{H}_{2}}O}}\,+\underset{Acid}{\mathop{{{H}_{2}}S}}\,\underset{{}}{\leftrightarrows}\underset{Acid}{\mathop{{{H}_{3}}{{O}^{+}}}}\,+\underset{Base}{\mathop{H{{S}^{-}}}}\,\]