Question

What is meant by (i) elements (ii) compounds, and (iii) mixtures ?Write down the names of two elements, two compounds and two mixtures.

Answer 1

• Element: An element is a substance that cannot be split up into two or more simpler substances by chemical methods. It contains only one type of atoms. Examples of elements include:

1. Non metals: Carbon and oxygen
2. Metals: Aluminum, iron, copper, gold, mercury, and lead.

• Compound: A compound is a substance consisting of two or more elements combined chemically in a fixed proportion by mass.
  Examples: Water, sodium chloride, calcium carbonate etc.
• Mixture: – A mixture is a substance  that is made up of two or more different kinds of particles or two or more pure substances mixed together by a physical process. Examples: Air, milk, wood, soil etc.