Question

An element Y exists as yellow solid, it shows catenation and allotropy? The element Y forms two types of oxides which are also the products of thermal decomposition of ferrous sulphate. These gases are the major cause of air pollution.

What is the nature (acidic or basic) of these oxides.

Answer 1

Step-1: Introduction

The linkage into atoms chain of the same element is catenation.

An element that can exhibit in many different form in the alike physical state is allotropy.

The element exist as yellow solid, showing catenation and allotropy is Sulphur ($\mathrm{S}$).

Step-2: Decomposition of Ferrous sulphate

Sulphur forms Sulphur dioxide (${\mathrm{SO}}_2$) and Sulphur trioxide (${\mathrm{SO}}_3$) which are the two types of oxides.

Ferric oxide (${\mathrm{Fe}}_2{\mathrm{O}}_3$), Sulphur dioxide and Sulphur trioxide are formed by decomposing Ferrous sulphate (${\mathrm{FeSO}}_4$).

$2{\mathrm{FeSO}}_4\to {\mathrm{Fe}}_2{\mathrm{O}}_3+{\mathrm{SO}}_2+{\mathrm{SO}}_3$

Step-3: Nature of oxides

Sulphur dioxide is acidic and that is poisonous when soluble in water to form sulphurous acid (${\mathrm{H}}_2{\mathrm{SO}}_3$). This gas is mainly used in can juice refining and sulphuric acid manufacture.

Sulphur trioxide is Lewis acidic gas due to presence of three electron region Sulphur atom that combines with water (${\mathrm{H}}_2\mathrm{O}$) and Calcium oxide ($\mathrm{CaO}$) to give Sulphuric acid (${\mathrm{H}}_2{\mathrm{SO}}_4$) and Calcium sulphate (${\mathrm{CaSO}}_4$) respectively.

Final answer

Therefore, these oxides are acidic in nature.