Question

Statement 1: \[{B_2}{O_3}\] is acidic.
Statement 2: \[A{l_2}{O_3}\]and \[G{a_2}{O_3}\] are amphoteric.
Statement 3: \[I{n_2}{O_3}\]and \[T{l_2}O\] are basic in nature.
The number of correct statements is:
1. 1,2
2. 2,3
3. 3,1
4. 1,2,3

Answer 1

Hint: The change of oxides nature as a move from left to right in the periodic table:
\[very\,basic \to less\,basic \to amphoteric \to less\,acidic \to very\,acidic\]

Complete Step by Step Solution:
1. Acidic oxides: The oxides of the non-metallic elements that form acidic solutions when reacting with water are called acidic oxides. For example, Boric acid
2. Basic oxides: The element of oxides form hydroxides in the form of \[A - O - H\]in an aqueous solution are called basic oxide. For example, Magnesium oxide
3. Amphoteric: The compound is either a neutral molecule or ionic molecule that can act as both acid or base and is called amphoteric oxide. For example, water behaves like an amphoteric molecule because it reacts with both acid (\[HCl\]) and base(\[N{H_3}\]).
4. Boron is a group 13 and period 2 element in the periodic table. The metallic property or electropositivity increases with a decrease in the acidity as moves down. When Boron trioxide reacts with the water then it forms Boric acid and the Boron oxide is acidic in nature.
\[{B_2}{O_3}(s) + {H_2}O(l) \to {H_3}B{O_3}(s)\]
5. Aluminium oxide is insoluble in water but it reacts with both acidic or basic aqueous solutions to form a soluble compound. So, the nature of Aluminium oxide is amphoteric.
The reaction of Aluminium oxide with acid,
\[A{l_2}{O_3}(s) + 6HCl(aq) \to 2AlC{l_3}(aq) + 3{H_2}O(l)\]
The reaction of Aluminium oxide with base,
\[A{l_2}{O_3}(s) + 2NaOH(aq) \to 2NaAl{O_2}(aq) + {H_2}O(l)\]
6. Gallium oxide is also an amphoteric character because it reacts with both acid and base to form Gallate and Hydrogen gas.
The reaction of Gallium oxide with acid,
\[G{a_2}{O_3}(s) + 6HCl(aq) \to 2GaC{l_3}(aq) + 3{H_2}O(l)\]
The reaction of Gallium oxide with base,
\[G{a_2}{O_3}(s) + 6KOH(s) \to 2Ga{(OH)_3}(s) + 3{K_2}O(s)\]
7. The atomic radii increase as they move down in the periodic table which means it is very difficult for the nucleus to dominate over the valence shell electrons. Therefore, there is an increase in the tendency to release the electrons with the increase in the metallic character that increases the basicity of the oxides. Basic oxides also depend on the oxidation state which means the least oxidation state compound has more basic in nature. Thallium oxide is more basic as compared to Indium oxide because it has the largest atomic radii and also the least oxidation state.
Thus, Option (4) is correct.

Additional information:
1. Acidic oxides are covalent compounds while basic oxides are ionic compounds.
2. Acidic oxides react with bases to form salt and water. Similarly, basic oxides react with acids and dissolve to form salt and water.

Note: If the electronegativity of an element is greater than 2.1, the \[O - H\] bond breaks, and \[{H^ + }\] is liberated, then the element is an acid, and these elements are generally non-metals. In the case of a metal, the electronegativity will be less than 2.1, and it's the oxides bond that breaks, allowing \[O{H^ - }\] to be liberated and the solution to become basic.