Available Answers

1. 1.

   Choose the correct answer.

   1. Which of the following chemist is well-known for hiss work on the Periodic Table?
      1. John Dalton
      2. Henry Cavendish
      3. Henry Moseley
      4. Joseph priestly
   2. Identify the scientist who discovered oxygen.
      1. Joseph Priestly
      2. Henry Cavendish
      3. john Daalton
      4. Henry Moseley
   3. Which of the following apparatus is used for measuring small quantities off liquids accurately?
      1. Measuring cylinder
      2. Beaker
      3. Pipette
      4. Watch glass
   4. Funnel is used for
      1. stirring and mixing liquids
      2. filtering solutions and transferring liquids
      3. measuring a definite volume of liquid
      4. heating or evaporating liquids
   5. A gas jar is used to
      1. heat substances in the laboratory
      2. collect gas
      3. add liquid reactants into the flask
      4. ground solid substances to powder
   6. Which of the following is a man-made fibre?
      1. Silk
      2. Cotton
      3. Nylon
      4. Linen
2. 2.

   Fill in the blanks.

   1. ________________, ________________, ________________ and ________________ help to increase thee production of food crops.
   2. Discovery of a number of ________________ has helped to increase the lifespan of human beings.
   3. DDT and BHC are examples of ________________.
   4. A ________________ is used to distribute heat uniformly so that the glass apparatus does not crack on heating.
   5. Urea i an important ________________.
   6. ________________ is famous for the discovery and description of the properties of hydrogen gas.
   7. ________________ is a chemical used for preserving food.
   8. ________________ is a system of acquiring knowledge using observation and experimentation.
   9. ________________ is a stand with three iron legs used to support glass apparatus while heating.
   10. ________________ or ________________ is used to heat substances in the laboratory.
   11. Kohl used for darkening eyelid consists of powdered ________________.
   12. ________________ used in food may be harmful.
3. 3.

   Write True (T ) or False (F) against the following statements:

   1. John Dalton formulated the Atomic Theory of Matter.
   2. Burette is used to pour liquids dropwise into a container by opening the tap at the bottom.
   3. TNT is a medicine used to kill germs and cure various diseases.
   4. A tripod stand ensures uniform distribution of heat to the glass apparatus placed on it.
   5. Louis Pasteur developed the process of pasteurisation.
   6. Tea and coffee get their flavour from the salts present in them.
4. 4.

   Match the following :

   Column A	Column B
   1. Organic Chemistry	a. Man-made elastic fibre
   2. Antiseptics	b. Used to heat or evaporate substances
   3. Test tube	c. Made of hard or pyrex glass
   4. China dish	d. Knowledge
   5. Scientia	e. Branch of Chemistry
   6. Lycra	f. used to kill germs

    

5. 5.

   What is Chemistry?

6. 6.

   Name three glass apparatus used to measure a definite volume of a liquid.