Some Basic Concepts of Chemistry - Test Papers


CLASS - XI CHEMISTRY (Basic Concepts of Chemistry)

General Instruction:

  • All questions are compulsory.
  • Marks are given alongwith their questions.

1. What is chemistry?

2. How has chemistry contributed towards nation’s development?

3. Differentiate solids, liquids & gases in terms of volume & shapes.

4. Name the different methods that can be used for separation of components of a mixture.

5. Classify following as pure substances and mixtures – Air, glucose, gold, sodium and milk.

6. What is the difference between molecules and compounds? Give examples of each.

7. How can we separate the components of a compound?

8. How can we say that sugar is solid and water is liquid?

9. How is matter classified at macroscopic level?

10. Classify following substances as element, compounds and mixtures – water, tea, silver, steel, carbondioxide and platinum.

CLASS - XI CHEMISTRY (Basic Concepts of Chemistry)

Ans 1. Chemistry is the branch of science that studies the composition, properties and interaction of matter.
Ans 2. Chemical principles are important in diverse areas such as weather patterns, functioning of brain, operation of a computer, chemical industries, manufacturing , fertilizers, alkalis, acids, salts, dyes, polymers, drugs, soaps, detergents, metals, alloys, contribute in a big way to national economy.
Ans 3.





1. VolumeDefiniteDefiniteNot definite
2. ShapeFixedNot fixed, take the shape of container,Not fixed, takes the shape of the container

Ans 4. The components of a mixture can be separated by physical methods like handpicking, filtrations, crystallization, distillation etc.  
Ans 5.

Pure SubstancesMixtures

Ans 6. Molecules consist of different atoms or same atoms. e.g. molecule of hydrogen contains two atoms of hydrogen where as molecule of water contain two atoms of hydrogen and one of oxygen.
Compound is formed when two or more than two different atoms combine in fire propo  e.g. water –rtion carbondioxide, sugar etc.
Ans 7. The constituents of a compound can not be separated by physical methods. They can only be separate by chemical methods.
Ans 8. Sugar has close packing of constituent particles, have its own volume and shape therefore, it can be said to be solid whereas in water the constituent particles are not as closely packed as in solid. It has definite volume but not definite shape. Therefore it is a liquid.
Ans 9. Macroscopic classification of matter –

Ans 10.