Which of the following is an element ?
(A) Ruby
(B) Sapphire
(C) Emerald
(D) Diamond
Important Questions on General Science
Sodium metal is kept under--
(A) Water
(B) Alcohol
(C) Petrol
(D) Kerosene
Bromine is --
(A) A colourless gas insoluble in water
(B) A highly inflammable gas
(C) A black solid
(D) A red liquid
Permanent hardness of water can be removed by adding--
(A) Potassium permanganate
(B) Chlorine
(C) Bleaching powder
(D) Washing soda
Which of the following substances is a bad conductor of electricity but a good conductor of heat ?
(A) Asbestos
(B) Celluloid
(C) Purspecks
(D) Mica
Which of the following pairs does not contain a coinage metal ?
(A) Copper and gold
(B) Silver and gold
(C) Zinc and gold
(D) Copper and silver
The filament of an electric bulb is made of--
(A) Iron
(B) Nichrome
(C) Tungsten
(D) Graphite
The two elements that are frequently used for making transistors are--
(A) Boron and aluminium
(B) Silicon and germanium
(C) Iridium and tungsten
(D) Niobium and columbium
Which of the following gases is not known as a greenhouse gas?
(A) Carbon dioxide
(B) Methane
(C) Nitrous oxide
(D) Chlorofluorocarbons
