Q.1
When iron rusts, its weight
Q.2
Air is said to be saturated when :
Q.3
For extinguishing fire, we use
Q.4
What are the number of moles of CO2 which contains 16 g of oxygen?
Q.5
The octane number of zero is assigned to
Q.6
The metal that is used as a catalyst in the hydrogenation of oils is
Q.7
The oldest rocks in the earth's crust were once molten, and came from deep inside the earth. The molten rock, called magma, spewed out in volcanic eruptions during the earth's early life and solidified into hard rock's called
Q.8
The most electronegative element among the following is
Q.9
Highest percentage of carbon is found in which form of coal?
Q.10
Spirit in contact with body gives cool sensation because it is :
Q.11
Diamond is lustrous because
Q.12
The lightest gas which is non-inflammable is
Q.13
Carbon monoxide is an inflammable gas. Which one of the following is also inflammable?
Q.14
Ozone layer of atmosphere absorbs:
Q.15
The gas used to extinguish fire is
Q.16
The metal that is usually extracted from sea water is
Q.17
The National Chemical Laboratory is situated in
Q.18
Dry powder fire extinguishers contain
Q.19
The most abundant rare gas in the atmosphere is
Q.20
The nucleus of a hydrogen atom consists of
Q.21
A metal is exposed to the atmosphere for sometime. It becomes coated with green carbonate. The metal must be
Q.22
The most abundant inert gas in the atmosphere is
Q.23
The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is
Q.24
The metal used to recover copper from a solution of copper sulphate is
Q.25
The main source of carbon monoxide is
Q.26
The biogas used for cooking is a mixture of which of the following?
Q.27
Dry ice is
Q.28
Preparation of ‘Dalda or Vanaspati’ ghee from vegetable oil utilizes the following process :
Q.29
When Hydrogen starts burning in air, it produces ?
Q.30
Air shows the property of
Q.31
Which of the following could be used as fuel in propellant or rockets ?
Q.32
Which among the following coal contains 90 per cent of carbon?
Q.33
Major portion of the earth’s crust is mainly constituted by
Q.34
The method of concentrating the ore which makes use of the difference in density between ore and impurities is called
Q.35
The inert gases are ____ in water.
Q.36
Equal masses of oxygen, hydrogen and methane are kept under identical conditions. The ratio of the volumes of gases will be
Q.37
Dry ice is the solid form of :
Q.38
The heat required to raise the temperature of body by 1 K is called
Q.39
The major constituent of gobar gas is
Q.40
The material used in the manufacture of lead pencil is
Q.41
Which one among the following is not a mixture?
Q.42
Litmus is obtained from
Q.43
Which among the following is pure matter ?
Q.44
Colour imparted to the Bunsen flame by strontium salt is
Q.45
Which of the following is not a noble gas ?
Q.46
The gas which turns into liquid at the lowest temperature among the following is
Q.47
The most abundant constituent of atmospheric air is :
Q.48
Which gas is used for converting vegetable oils into saturated fats ?
Q.49
In surgery, metal pins are used for joining together broken bones. These metal pins remain uncorroded in the body. What is the material of these pins?
Q.50
The molecular formula of phosphorous is
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