Q. Brass gets discoloured in air because of the presence of which of the following gases in air?
(a) Oxygen
(b) Hydrogen sulphide
(c) Carbon dioxide
(d) Nitrogen
Answer
Answer: (b) Hydrogen sulphide
Q. Which of the following is a non metal that remains liquid at room temperature?
(a) Phosphorous
(b) Bromine
(c) Chlorine
(d) Helium
Answer
Answer: (b) Bromine
Q. Chlorophyll is a naturally occurring chelate compound in which central metal is
(a) copper
(b) magnesium
(c) iron
(d) calcium
Answer
Answer: (b) magnesium
Q. Which of the following is used in pencils?
(a) Graphite
(b) Silicon
(c) Charcoal
(d) Phosphorous
Answer
Answer: (a) Graphite
Q. Which of the following metals forms an amalgam with other metals?
(a) Tin
(b) Mercury
(c) Lead
(d) Zinc
Answer
Answer: (b) Mercury
Q. Chemical formula for water is
(a) NaAlO2
(b) H2O
(c) Al2O3
(d) CaSiO3
Answer
Answer: (b) H2O
Q. The gas usually filled in the electric bulb is
(a) nitrogen
(b) hydrogen
(c) carbon dioxide
(d) oxygen
Answer
Answer: (a) nitrogen
Q. Washing soda is the common name for
(a) Sodium carbonate
(b) Calcium bicarbonate
(c) Sodium bicarbonate
(d) Calcium carbonate
Answer
Answer: (a) Sodium carbonate
Explanation:
What is the scientific name for washing soda?
Sodium carbonate (also known as washing soda or soda ash), Na2CO3 is a sodium salt of carbonic acid.
Scientific name for baking soda?
Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula NaHCO3. Sodium bicarbonate is a white solid that is crystalline but often appears as a fine powder. Since it has long been known and is widely used, the salt has many related names such as baking soda, bread soda, cooking soda, and bicarbonate of soda.
Q. Quartz crystals normally used in quartz clocks etc. is chemically
(a) silicon dioxide
(b) germanium oxide
(c) a mixture of germanium oxide and silicon dioxide
(d) sodium silicate
Answer
Answer: (a) silicon dioxide
Q. Which of the gas is not known as green house gas?
(a) Methane
(b) Nitrous oxide
(c) Carbon dioxide
(d) Hydrogen
Answer
Answer: (d) Hydrogen
Explanation:
In order, the most abundant greenhouse gases in Earth’s atmosphere are:
* water vapor
* carbon dioxide
* methane
* nitrous oxide
* ozone
* chlorofluorocarbons
Q. Bromine is a
(a) black solid
(b) red liquid
(c) colourless gas
(d) highly inflammable gas
Answer
Answer: (b) red liquid
Q. The hardest substance available on earth is
(a) Gold
(b) Iron
(c) Diamond
(d) Platinum
Answer
Answer: (c) Diamond
Q. The variety of coal in which the deposit contains recognisable traces of the original plant material is
(a) bitumen
(b) anthracite
(c) lignite
(d) peat
Answer
Answer: (d) peat
Q. Tetraethyl lead is used as
(a) pain killer
(b) fire extinguisher
(c) mosquito repellent
(d) petrol additive
Answer
Answer: (d) petrol additive
Q. Which of the following is used as a lubricant?
(a) Graphite
(b) Silica
(c) Iron Oxide
(d) Diamond
Answer
Answer: (a) Graphite
Q. The inert gas which is substituted for nitrogen in the air used by deep sea divers for breathing, is
(a) Argon
(b) Xenon
(c) Helium
(d) Krypton
Answer
Answer: (c) Helium
Q. The gases used in different types of welding would include
(a) oxygen and hydrogen
(b) oxygen, hydrogen, acetylene and nitrogen
(c) oxygen, acetylene and argon
(d) oxygen and acetylene
Answer
Answer: (d) oxygen and acetylene
Q. The property of a substance to absorb moisture from the air on exposure is called
(a) osmosis
(b) deliquescence
(c) efflorescence
(d) desiccation
Answer
Answer: (b) deliquescence
Q. In which of the following activities silicon carbide is used?
(a) Making cement and glass
(b) Disinfecting water of ponds
(c) cutting very hard substances
(d) Making casts for statues
Answer
Answer: (c) cutting very hard substances
Q. The average salinity of sea water is
(a) 3%
(b) 3.5%
(c) 2.5%
(d) 2%
Answer
Answer: (b) 3.5%
Q. When an iron nail gets rusted, iron oxide is formed
(a) without any change in the weight of the nail
(b) with decrease in the weight of the nail
(c) with increase in the weight of the nail
(d) without any change in colour or weight of the nail
Answer
Answer: (c) with increase in the weight of the nail
Q. Galvanised iron sheets have a coating of
(a) lead
(b) chromium
(c) zinc
(d) tin
Answer
Answer: (c) zinc
Q. Among the various allotropes of carbon,
(a) coke is the hardest, graphite is the softest
(b) diamond is the hardest, coke is the softest
(c) diamond is the hardest, graphite is the softest
(d) diamond is the hardest, lamp black is the softest
Answer
Answer: (c) diamond is the hardest, graphite is the softest
Q. The group of metals Fe, Co, Ni may best called as
(a) transition metals
(b) main group metals
(c) alkali metals
(d) rare metals
Answer
Answer: (a) transition metals
Q. Heavy water is
(a) deuterium oxide
(b) PH7
(c) rain water
(d) tritium oxide
Answer
Answer: (a) deuterium oxide
Q. The chemical (ethyl mercaptan) added to the otherwise odourless LPG cooking gas for imparting a detectable smell to the gas is a compound of
(a) bromine
(b) fluorine
(c) chlorine
(d) sulphur
Answer
Answer: (d) sulphur
Q. The element common to all acids is
(a) hydrogen
(b) carbon
(c) sulphur
(d) oxygen
Answer
Answer: (a) hydrogen
Q. Non stick cooking utensils are coated with
(a) Teflon
(b) PVC
(c) black paint
(d) polystyrene
Answer
Answer: (a) Teflon
Q. Monazite is an ore of
(a) titanium
(b) zirconium
(c) iron
(d) thorium
Answer
Answer: (d) thorium
Q. Carbon, diamond and graphite are together called
(a) allotropes
(b) isomers
(c) isomorphs
(d) isotopes
Answer
Answer: (a) allotropes
Q. Potassium nitrate is used in
(a) medicine
(b) fertiliser
(c) salt
(d) glass
Answer
Answer: (b) fertiliser
Q. Permanent hardness of water may be removed by the addition of
(a) sodium carbonate
(b) alum
(c) potassium permanganate
(d) lime
Answer
Answer: (a) sodium carbonate
Q. Soda water contains
(a) carbonic acid
(b) sulphuric acid
(c) carbon dioxide
(d) nitrous acid
Answer
Answer: (c) carbon dioxide
Q. The most important ore of aluminium is
(a) galena
(b) calamine
(c) calcite
(d) bauxite
Answer
Answer: (d) bauxite
Explanation:
Bauxite is an aluminium ore and is the main source of aluminium.
Q. Most soluble in water is
(a) camphor
(b) sulphur
(c) common salt
(d) sugar
Answer
Answer: (d) sugar
Q. Which of the following was to be discovered first in the chromospheres of the sun?
(a) Krypton
(b) Xenon
(c) Neon
(d) Helium
Answer
Answer: (d) Helium
Q. Which of the following is in liquid form at room temperature?
(a) Lithium
(b) Sodium
(c) Francium
(d) Cerium
Answer
Answer: (c) Francium
Q. Sodium metal is kept under
(a) petrol
(b) alcohol
(c) water
(d) kerosene
Answer
Answer: (d) kerosene
Q. Which of the following are the ingredients of gun metal?
(a) Iron, Zinc, Titanium
(b) Iron, tin
(c) Iron, Brass, Tin
(d) Copper, Tin
Answer
Answer: (d) Copper, Tin
Q. From which mineral is radium obtained?
(a) Rutile
(b) Haematite
(c) Limestone
(d) Pitchblende
Answer
Answer: (d) Pitchblende
Q. What is laughing gas?
(a) Nitrous Oxide
(b) Carbon monoxide
(c) Sulphur dioxide
(d) Hydrogen peroxide
Answer
Answer: (a) Nitrous Oxide
Q. Actinides are the elements with atomic numbers from
(a) 97 to 104
(b) 101 to 115
(c) 89 to 103
(d) 36 from 43
Answer
Answer: (c) 89 to 103
Q. 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
Answer
Answer: (b) silicon and germanium
Q. The filament of an electric bulb is made of
(a) tungsten
(b) nichrome
(c) graphite
(d) iron
Answer
Answer: (a) tungsten
Q. Diamond is an allotropic form of
(a) germanium
(b) carbon
(c) silicon
(d) sulphur
Answer
Answer: (b) carbon
Q. In fireworks, the green flame is produced because of
(a) sodium
(b) barium
(c) mercury
(d) potassium
Answer
Answer: (b) barium
Q. Permanent hardness of water can be removed by adding
(a) chlorine
(b) washing soda
(c) potassium permanganate
(d) bleaching powder
Answer
Answer: (b) washing soda
Q. Marsh gas is
(a) nitrogen
(b) ethane
(c) methane
(d) hydrogen
Answer
Answer: (c) methane
Q. LPG consists of mainly
(a) methane, ethane and hexane
(b) ethane, hexane and nonane
(c) methane, hexane and nonane
(d) methane, butane and propane
Answer
Answer: (d) methane, butane and propane
Q. Air is a/an
(a) compound
(b) element
(c) electrolyte
(d) mixture
Answer
Answer: (d) mixture
Q. Production of chlorofluorocarbons (CFC) gas which is proposed to be banned in India, is used in which of the following domestic products?
(a) Television
(b) Refrigerator
(c) Tube light
(d) Cooking gas
Answer
Answer: (b) Refrigerator
Q. Balloons are filled with
(a) nitrogen
(b) helium
(c) oxygen
(d) argon
Answer
Answer: (b) helium
Q. Which of the following does not contain a coinage metal?
(a) Silver and Gold
(b) Zinc and Gold
(c) Copper and Silver
(d) Copper and Gold
Answer
Answer: (b) Zinc and Gold
Q. Which metal pollute the air of a big city?
(a) Copper
(b) Chromium
(c) Lead
(d) Cadmium
Answer
Answer: (c) Lead
Q. Bell metal is an alloy of
(a) nickel and copper
(b) zinc and copper
(c) brass and nickel
(d) tin and copper
Answer
Answer: (d) tin and copper
Q. Water is a good solvent of ionic salts because
(a) it has a high specific heat
(b) it has no colour
(c) it has a high dipole moment
(d) it has a high boiling point
Answer
Answer: (c) it has a high dipole moment
Q. Which of the following is not an isotope of hydrogen?
(a) Tritium
(b) Deuterium
(c) Protium
(d) Yttrium
Answer
Answer: (d) Yttrium
Q. The main constituents of pearls are
(a) calcium oxide and ammonium chloride
(b) calcium carbonate and magnesium carbonate
(c) aragonite and conchiolin
(d) ammonium sulphate and sodium carbonate
Answer
Answer: (b) calcium carbonate and magnesium carbonate
Q. Amalgams are
(a) highly coloured alloys
(b) alloys which contain mercury as one of the contents
(c) alloys which have great resistance to abrasion
(d) alloys which contain carbon
Answer
Answer: (b) alloys which contain mercury as one of the contents
Q. Which of the following is the lightest metal?
(a) Mercury
(b) Lithium
(c) Lead
(d) Silver
Answer
Answer: (b) Lithium
Q. Which of the following metals remain in liquid for under normal conditions?
(a) Radium
(b) Zinc
(c) Uranium
(d) Mercury
Answer
Answer: (d) Mercury
Q. Potassium Permanganate is used for purifying drinking water, because
(a) it is a sterilising agent
(b) it dissolves the impurities of water
(c) it is a reducing agent
(d) it is an oxidising agent
Answer
Answer: (d) it is an oxidising agent
Q. Which of the following is an element?
(a) Ruby
(b) Sapphire
(c) Emerald
(d) Diamond
Answer
Answer: (d) Diamond