Railway recruitment board (RRB) Examinations is the easiest exam comparing to other competitive examinations because there is no English language section and mode of examination is in English (default) and 14 other languages.
RRB examinations like ALP, JE, and NTPC consists of four major parts i.e. Mathematics, Logical reasoning, General awareness and General science. The general science section comprises of 30 marks in CBT 1 and 15 marks in Physics & Chemistry in CBT2 which plays a vital role in boosting up the score for both CBT 1 and CBT 2. So here by we are providing the new pattern questions for improving your marks in both the stages of RRB examinations with detail explanation.
1) Which of the following is not a homogenous mixture?
a) Blood Plasma
b) Corn oil
c) Iodised salt
d) White Vinegar
2) Which of the following is a compound?
3) Which of the following is not a pure substance?
4) Purification of drinking water from sea water can be done by
a) Steam distillation
d) Reverse osmosis
5) Which of the following is not a physical change?
a) Melting of ice cube
b) Ripening of fruits
c) Casting silver in a mould
d) Evaporation of water from surface of sea
6) A mixture of acetone and methyl alcohol can be separated by
b) Fractional distillation
c) Steam distillation
d) Reverse osmosis
7) Which of the following is not true?
a) Fluidity is maximum in liquid state.
b) Boiling point increases in the presence of impurities.
c) Elements contain only single type of atoms.
d) Inter-molecular force is maximum in solids.
8) ‘At constant pressure, volume of a fixed mass of a gas is directly proportional to its absolute temperature’ is defined by
a) Gay Lussac’s Law
b) Boyle’s Law
c) Combined gas law
d) Charle’s Law
9) Avagadro number is given by
a) 6.024 x 1023
b) 6.023 x 1023
c) 6.023 x 1024
d) 6.024 x 1024
10) Critical temperature of oxygen is
1) Answer: c)
Iodised salt is a heterogeneous mixture because salt can be separated from iodine.
2) Answer: a)
Alcohol is a combination of two or more elements. So it is a compound.
3) Answer: d)
Milk is a combination of water, fat, carbohydrate, protein and other nutrients. So it is a complex mixture.
4) Answer: d)
Reverse osmosis is a technique in which solvent molecules move from the solution of higher concentration to solution of lower concentration when these are separated by semipermeable membrane. Purification of drinking water from sea water can be done by reverse osmosis method.
5) Answer: b)
Physical change only affects the physical properties like colour, hardness, density, melting point, etc., of matter. But chemical change affects the composition and chemical properties of matter. Ripening of fruit involve a chemical change.
6) Answer: b)
Fractional distillation is used to separate liquids having very less difference in their boiling points. It is used to obtain pure diesel, kerosene oil, petrol from crude oil. A mixture of acetone(329K) and methyl alcohol(338K) can be separated by this method.
7) Answer: a)
Fluidity is maximum in gaseous state.
8) Answer: d)
Charle’s law states that at constant pressure, volume of a fixed mass of a gas is directly proportional to its absolute temperature. V ∝ T.
9) Answer: b)
Number of molecules present in 12g of C-12 is called 1 mole, i.e.,
1 mol= 6.023 x 1023 = Avagadro number
10) Answer: c)
Temperature above which a gas cannot be liquefied is known as critical temperature. Critical temperature of oxygen is 154.6K.