1. The element required for Solar energy conversion _____
(D) Ultra pure carbon
2. Potassium Permanganate is used for purifying drinking water, because _____
(A) It dissolves the impurities of water
(B) It is a sterilizing agent
(C) It is an oxidising agent
(D) It is a reducing agent.
3. Water is a good solvent of ionic salts because ______
(A) It has no colour
(B) It has a boiling point
(C) It has a high dipole moment
(D) It has a high specific heat
4. In which type of rocks are metals like Gold and Copper mostly found ?
(A) Old igneous
(B) Old sedimentary
(C) Old metamorphic
(D) New metamorphic
5. Which of the following gases is lighter than air ?
(A) Carbon dioxide
6. The percentage of carbon is the least in —
(A) Grey cast iron
(B) Wrought iron
(C) White cast iron
7. Which of the following is the best conductor of electricity ?
8. Permanent hardness of water, due to sulphates of the metal, can be destroyed by the use of —
(D) None of these
9. Liquefied Petroleum gas (LPG) consists of mainly _____
(A) Methane, Ethane and Hexane
(B) Ethane, Hexane and Nonane
(C) Methane, Butane and Propane
(D) Methane, Hexane and Nonane
10. The metal that is present in Photo Films is _____
11. Parmanent hardness of water may be removed by the addition of ______
(B) Sodium Carbonate
(D) Potassium Permanganate
12. Potassium nitrate is used in ________
13. Which of the following is in liquid form at room temperature?
14. Which of the following is basis of the modern periodic table?
(A) Atomic mass
(B) Atomic number
(C) Atomic size
(D) Atomic volume
15. Of the following metals, which one pollutes the air of a big city ?