Question

An element X on reacting with oxygen forms an oxide X2O. this oxide dissolves in water and turns blue litmus red. a) Identify the element X and mention the nature of the compound formed. b) Write a balanced chemical equation for the above reaction

Answer 1

Answer:

The unknown element is Carbon.

(a) X is Carbon, its oxide is of acidic nature

(b) C+ O2 → CO2

Explanation:

We are given an unknown element that reacts with oxygen.

X + O2 → XO2

It is given that the oxide XO2 turns blue litmus red which is shown by acids, so XO2 is an acidic oxide. Also X will be a Non metal because Non metallic oxide is Acidic in nature.

The Oxide XO2 is dissolving is water. The oxide upon reacting with water will give an Acid.

XO2 type of oxide is found in the 14th group of the periodic table generally

So we have options like C, Si and Ge as these only have the Acidic oxide.

But when it comes to reactivity with water Only Carbon satisfies the need so the unknown element X is C.

CO2 + H2O → H2CO3 which is an acid.

(a) Element X is Carbon (C), The nature of the compound formed is Acidic.

(b) The reaction given will be as follows

     C+ O2 → CO2

Therefore the unknown element is Carbon.