Pure substances
Pure substances: Overview
This topic highlights the pure substances and their types based on chemical composition. It elaborates elements with examples describing their physical and chemical properties. It also shows how a compound is composed of two or more elements.
Important Questions on Pure substances

What is the solubility of hydrogen sulphide gas in water.

Hydrogen sulphide has a characteristic pungent smell.

Write any two properties of hydrogen sulphide gas.

Explain the classification of substances on the basis of their physical state.


Sulphuric acid is an example for compound. Justify.

Identify the compounds in the following:
Soil, Sulphuric acid, Gold, Air, Water, Ammonia, Iron.

The substance formed by the chemical combination of two or more than two elements in a definite ratio is termed as a _____.

What are metalloids? Explain the uses of some metalloids.

Compounds are formed of the same type of particles.

Compounds can be easily separated into their constituents by physical processes.

Give one or two word(s) for the following:
A pure substance made up of only one kind of particles.

Differentiate between compounds and mixtures.

Differentiate between: Mixtures and Compounds.

What are the combining elements of hydrogen chloride and ammonia?




The elements are made up of only _____ type of particles.
(Chromatography, Valency, Cuprum, Negatively, , one, , Positively, Separating funnel)
