Exercise 1

Question 1 :

The nucleus of an atom consists of


A). electrons and neutrons
B). electrons and protons
C). protons and neutrons
D). All of the above
Answer : Option C

Question 2 :

The number of moles of solute present in 1 kg of a solvent is called its


A). molality
B). molarity
C). normality
D). formality
Answer : Option A

Question 3 :

The most electronegative element among the following is


A). sodium
B). bromine
C). fluorine
D). oxygen
Answer : Option C

Question 4 :

The metal used to recover copper from a solution of copper sulphate is


A). Na
B). Ag
C). Hg
D). Fe
Answer : Option D

Question 5 :

The metallurgical process in which a metal is obtained in a fused state is called


A). smelting
B). roasting
C). calcinations
D). froth floatation
Answer : Option A

Question 6 :

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


A). granite
B). basalt
C). igneous rocks
D). sedimentary rocks
Answer : Option C

Question 7 :

The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is


A). Dalton's law
B). Gay Lussac's law
C). Henry's law
D). Raoult's law
Answer : Option C

Question 8 :

The gas present in the stratosphere which filters out some of the sun's ultraviolet light and provides an effective shield against radiation damage to living things is


A). helium
B). ozone
C). oxygen
D). methane
Answer : Option B

Question 9 :

The most commonly used bleaching agent is


A). alcohol
B). carbon dioxide
C). chlorine
D). sodium chlorine
Answer : Option C

Question 10 :

The nucleus of a hydrogen atom consists of


A). 1 proton only
B). 1 proton + 2 neutron
C). 1 neutron only
D). 1 electron only
Answer : Option A

Question 11 :

The heat required to raise the temperature of body by 1 K is called


A). specific heat
B). thermal capacity
C). water equivalent
D). None of the above
Answer : Option B

Question 12 :

The nuclear particles which are assumed to hold the nucleons together are


A). electrons
B). positrons
C). neutrons
D). mesons
Answer : Option D

Question 13 :

The octane number of zero is assigned to


A). 2-methyl octane
B). n-heptane
C). iso-octane
D). 3-methyl octane
Answer : Option B

Question 14 :

The metal that is used as a catalyst in the hydrogenation of oils is


A). Ni
B). Pb
C). Cu
D). Pt
Answer : Option A

Question 15 :

The most abundant rare gas in the atmosphere is


A). He
B). Ne
C). Ar
D). Xe
Answer : Option C

Question 16 :

The Latin word formica means ant. The name formic acid is derived from this Latin word because


A). this acid, in ancient times, was used to eliminate ant-hills
B). this corrosive acid is secreted by ants to drive away their enemies
C). this acid was first obtained by the distillation of ants
D). ants are attracted by the odour of this acid
Answer : Option C

Question 17 :

The ore which is found in abundance in India is


A). monazite
B). fluorspar
C). bauxite
D). magnetite
Answer : Option A

Question 18 :

The inherited traits of an organism are controlled by


A). RNA molecules
B). nucleotides
C). DNA molecules
D). enzymes
Answer : Option C

Question 19 :

The heat energy produced when the human body metabolises 1 gram of fat is


A). 30 KJ
B). 1 KJ
C). 39 KJ
D). 29 KJ
Answer : Option C

Question 20 :

What are the number of moles of CO2 which contains 16 g of oxygen?


A). 0.5 mole
B). 0.2 mole
C). 0.4 mole
D). 0.25 mole
Answer : Option A

Explanation :

One mole of CO2 has mass of 44 g and 32 g of O2. So 16 g of O2 have 22 g of CO2 or 0.5 moles of it.


Question 21 :

The main use of salt in the diet is to


A). make the taste of food better
B). produce in small amounts the hydrochloric acid required for the digestion of food
C). ease the process of cooking
D). increase the solubility of food particles in water
Answer : Option B