Question

Which of the following is an amphoteric oxide?
a.) \[{{V}_{2}}{{O}_{5}},C{{r}_{2}}{{O}_{3}}\]
b.) \[M{{n}_{2}}{{O}_{7}},C{{r}_{2}}{{O}_{3}}\]
c.) \[CrO,{{V}_{2}}{{O}_{5}}\]
d.) \[{{V}_{2}}{{O}_{5}},{{V}_{2}}{{O}_{4}}\]

Answer 1

Hint: An amphoteric oxide are those which can act as a base or as an acid. These types of elements show the properties of both acids and bases. Amphoteric oxides react with both acids and alkalis to form salt and water.

Complete step by step answer:
In chemistry, an amphoteric species is a molecule or ion which can react as an acid as well as a base. This word is derived from the Greek word ‘amphotericin’ which means both i.e. they show the properties resembling acid as well as base too.
Metallic oxides are known as amphoteric oxides which display both the basic and acidic nature. Elements that form amphoteric oxides exhibit some metals and some of the nonmetals characteristics.
Examples of amphoteric oxides are zinc oxide and aluminum oxide.
Out of all the examples given in the question only \[{{V}_{2}}{{O}_{5}},C{{r}_{2}}{{O}_{3}}\] exhibits the property of amphoteric oxides i.e. it can behaves as an acid or base. But \[M{{n}_{2}}{{O}_{7}},CrO,{{V}_{2}}{{O}_{4}}\] does not exhibit the property of amphoteric oxides.
So, the correct answer is “Option A”.

Note: Many metals form amphoteric oxides or hydroxides. Metal oxides which react with both acids as well as bases to produce salts and water are known as amphoteric oxides and Amphoteric hydroxides act as either Bronsted-Lowry bases (accepting protons) or Lewis acids (accepting an electron pair) depending on reaction conditions.