Question

Mercury(ii) oxide breaks down when it is heated to form?

1) oxygen gas and liquid gas mercury
2) mercury(ii) oxidemercury(ii) oxide oxygen
3) mercurymercury → mercury(ii) oxide oxygen
4) oxygen mercury

Answer 1

Mercury(II) oxide decomposes into liquid mercury and oxygen gas when heated, characterized by a color change from red to silver (option 1).

Step-by-step explanation:

When Mercury(II) oxide is heated, it breaks down into two elements: liquid mercury and oxygen gas. This chemical reaction is an example of a decomposition reaction, a type of reaction in which a compound is broken down into simpler substances.

The process can be represented by the chemical equation:

2HgO (s) → 2 Hg (l) + O₂ (g), where 's' denotes a solid, 'l' denotes a liquid, and 'g' denotes a gas. When Mercury(II) oxide, which is a red solid, is heated to temperatures above 500°C, it decomposes into silver-colored liquid mercury and invisible oxygen gas. Observing the color change from red to silver can indicate that the reaction has occurred.

Hence, the answer is option 1.