1521. Which one of the following statements is true ?

A. Gases donot conduct heat
B. The best conductors are non-metals
C. Conduction current occurs only in liquids
D. None of the statements is true *

1522. Ice can be changed to water by :

A. Adding more water molecules
B. Changing the motion of the water molecules *
C. Rearranging the atoms in water molecules
D. Destroying the atoms in water molecules

1523. The building block of elements are called :

A. Atoms *
B. Molecules
C. Compounds
D. Isotopes

1524. Boiling of an egg is change which is :

A. Physical *
B. Chemical
C. Physiological
D. Mrophological

1525. The temperature of liquid nitrogen is :

A. -32 degree centigrade
B. -80 degree centigrade
C. -100 degree centigrade
D. -196 degree centigrade *

1526. Which one of the following is an Al kali ?

A. Water
B. Vinegar
C. Lemon Juice
D. Slaked lime *

1527. If an alkali is slowly mixed to an acidic solution, the PH of the acidic solution will:

A. Increase *
B. Decrease
C. Increase to 7 and then decrease
D. Decrease to 7 and then increase

1528. The usual raw material for ceramics, generally found beneath the top soil is ?

A. Sand
B. Silt
C. Clay *
D. Plaster of paris

1529. Polyamides are synthetic polymers commonly known as :

A. Synthetic rubber
B. Nylon *
C. Cellulose
D. Protein

1530. Telephone was invented in 1876 in America by :

A. Marconi
B. Galileo
C. John Beard
D. Graham Bell *