question_answer

For \[{{H}_{3}}P{{O}_{3}}\] and \[{{H}_{3}}P{{O}_{4}}\], the correct choice is

A) \[{{H}_{3}}P{{O}_{3}}\] is dibasic and reducing

B) \[{{H}_{3}}P{{O}_{4}}\] is diabasic and non-reducing

C) \[{{H}_{3}}P{{O}_{4}}\] is tribasic and reducing

D) \[{{H}_{3}}P{{O}_{4}}\] is tribasic and non-reducing

Correct Answer: A

Solution :

[a] The structure of \[{{H}_{3}}P{{O}_{3}}\] is as given below. There are only two \[-OH\] groups and hence it is dibasic. The oxidation number of P in this acid is +3, whereas P may have +5 oxidation state also. Therefore, \[{{H}_{3}}P{{O}_{3}}\] can be oxidised which means \[{{H}_{3}}P{{O}_{3}}\] is a reducing agent.