2. •Charge – The coulomb
•Current – The ampere
•Potential Difference - The Volt
•Resistance - The ohm
•Resistivity – The ohm metre
•Energy – The joule
•Power – The watt
•Focal length – The metre
•Power of a lens – The dioptre.

3. Periods
Groups
i. The horizontal rows of elements
in the modern periodic table are
called as periods.
ii. There are seven periods in the
modern periodic table.
iii. The period number indicates the
number of electronic shells present
in an atom of every element
belonging to that period.
iv. Elements show gradual variation
in chemical properties along a
period.
i. The vertical columns of elements
in the modern periodic table are
called as groups.
ii. There are eighteen groups in the
modern periodic table.
ii. There are eighteen groups in the
modern periodic table.
iii. The group number indicates the
number of electrons in the
outermost shell of an atom of
every element belonging to that
group.
iv. Elements belonging to a
particular group show strong
resemblance in their chemical

4. Mendeleev's periodic table
Modern periodic table
i. In Mendeleev's periodic
table, elements were
arranged in an increasing
order of atomic weight.
ii. In Mendeleev's periodic
table there were 8 groups.
iii. In Mendeleev's periodic
table isotopes of same
elements were given different
positions.
iv. A correct position could
not be assigned to hydrogen
in the Mendeleev's periodic
table.
i. In Modern periodic table,
elements are arranged in an
increasing order of atomic
numbers.
ii. In modern periodic table,
there are 18 groups.
iii. In Modern periodic table
isotopes of same elements are
given same positions.
iv. Hydrogen has been placed
at the top of group I in
modern periodic table.

5. Inert gas elements
Normal elements
i. In the atoms of Inert gas
elements all the shells are
completely filled including
the outermost shell.
ii. These elements are placed
in zero group (group 18) of
modern periodic table.
iii. These elements have
stable electronic
configuration and hence,
they are chemically inactive.
iv. Their valency is zero.
i. In the atoms of Normal
elements only the outermost
shell is incompletely filled.
ii. These elements are placed
in groups 1 and 2 on the left
side and 13 to 17 on the right
side of modern periodic table.
iii. These elements do not
have stable electronic
configuration and hence,
they are chemically active.
iv. They normally show one
type of valency.

6. Normal Elements
Transition Elements
i. In the atoms of Normal
elements only the outermost
shell is incompletely filled.
ii. These elements are placed
in groups 1 and 2 on the left
side and 13 to 17 on the right
side of modern periodic table.
iii. They are included in s –
block and p – block of
modern periodic table.
iv. They normally show one
type of valency.
i. In the atoms of these
elements the last two shells
are incompletely filled.
ii. These elements are placed
in groups 3 to 12 in the
middle of the modern
periodic table.
iii. They are included in d –
block of modern periodic
table.
iv. They show variable
valency.

7. Transition elements
Inner transition elements
i. In the atoms of these
elements the last two shells
are incompletely filled.
ii. These elements are placed
in groups 3 to 12 in middle of
the modern periodic table.
iii. They are included in d –
block of the modern periodic
table.
i. In the atoms of these
elements the last three shells
are incompletely filled.
ii. These elements are placed
in two additional rows (i.e.
lanthanides and actinides)
called series, placed at the
bottom of the modern
periodic table.
iii. They are included in f block of modern periodic
table.

8. s – block elements
p – block elements
i. In modern periodic
table the groups 1 and 2
are included in s – block.
ii. These includes alkali
metals and alkaline earth
metals.
iii. They have 1 or 2
electrons in the last
shell.
i. In modern periodic
table the groups 13 to 17
and the zero group
elements are included in
p – block.
ii. These includes metals,
non – metals and
metalloids.
iii. They have 3 to 8
electrons in the last
shell.

9. Oxidation
Reduction
i. The chemical
reaction in which
reactants gain
oxygen or lose
hydrogen is called
oxidation.
ii.A reducing agent
undergoes
oxidation.
i. The chemical
reaction in which
reactants gain
hydrogen or lose of
oxygen is called
reduction.
ii.An oxidising agent
undergoes
reduction.

10. Voltmeter
Ammeter
i. A voltmeter is used to i. An ammeter is used to
measure the potential
measure the current in
difference between two
a circuit.
points.
ii.An ammeter is
ii.A voltmeter is
connected in series
connected in parallel to with the conductor, the
the conductor across
current through which
which the potential
is to be measured.
difference is to be
iii.An ammeter has a
measured.
very low resistance.
iii.A voltmeter has a very
high resistance.

11. Direct current
Alternating current
i. Direct current flows
i. Alternating current
only in one direction.
reverses its direction
ii.It cannot be used for
periodically with time.
large scale of electricity ii.It is used in household
of household purpose.
electrical appliances
iii.The frequency is zero.
such as an electric
heater, and electric
iron, a refrigerator, etc.
iii.The frequency of
alternating current in
India is 50 Hz.

12. Real image
Virtual image
i. A real image is formed i. A virtual image is
when the light rays
formed when the light
starting from an object
rays starting from an
meet after reflection or
object appear to meet
refraction.
after reflection or
ii.It can be projected on a refraction.
screen.
ii.It cannot be projected
iii.It is inverted with
on a screen.
respect to the object.
iii.It is erect with respect
to the object.

13. Convex lens
Concave lens
i. A convex lens has
i. A concave lens has
its surfaces bulging
its surfaces curved
outward.
inward.
ii.It is thicker in the
ii.It is thicker at the
middle than at the
edges than in the
edges.
middle.
iii.It can form a real
iii.It can form only a
image as well as
virtual image.
virtual image.

14. Metals
Non – metals
i. Metals have a lustre.
i. Non – metals have no
ii. They are generally good
lustre. Exception : Iodine
conductors of heal and
and diamond.
electricity.
ii. They are bad conductors of
iii.They are generally solids at
heal and electricity.
room temperature.
Exception: Graphite
Exception : Mercury and
iii.They are generally gases
Gallium are liquids.
and solids at room
iv.Metals form basic oxides.
temperature. Exception :
Bromine is a liquid.
iv.Non – metals form acidic or
neutral oxides.

15. Roasting
Calcination
i. In this process, the ore i. In this process, the ore
is heated strongly in
is heated strongly in
the presence of air.
the limited supply of
ii.In this process,
air.
sulphide ore is
ii.In this process,
converted into metal
carbonate ore is
oxide.
converted into metal
iii.During this process
oxide.
SO4 is given out.
iii.During this process
CO2 is given out.

16. Saturated hydrocarbons
Unsaturated hydrocarbons
i. In saturated hydrocarbons,
the carbon atoms are linked
to each other only by a
single covalent bonds.
ii. They contain only single
bond.
iii.These compounds are
chemically less reactive.
iv.Substitution reaction is a
characteristic property of
these hydrocarbons.
v. Their general formula is
CnH2n+2.
i. In unsaturated
hydrocarbons, the valencies
of carbon atoms are not
fully satisfied by single
covalent bonds.
ii. They contain carbon to
carbon double or triple
bonds.
iii.These compounds are
chemically more reactive.
iv.Addition reaction is a
characteristic property of
these hydrocarbons.
v. Their general formula is
CnH2n or CnH2n - 2.

17. Open chain
hydrocarbons
Closed chain
hydrocarbons
i. A hydrocarbon in
i. A hydrocarbon in
which the chain of
which the chain of
carbon atoms is not
carbon atoms is
cyclic is called the open present in a cyclic form
chain hydrocarbon.
or ring form is called
ii.All aliphatic
the closed chain
hydrocarbons contain
hydrocarbons.
open chains.
ii.All aromatic
hydrocarbons contain
closed chains.

18. Stomach
Small intestine
i. The stomach is the
broadest part of the
alimentary canal.
ii.Glands present in the
stomach wall produce
gastric juice.
iii.There is acidic
medium in the
stomach.
iv.Food gets partially
digested in the
stomach.
i. The small intestine is
the narrowest part of
the alimentary canal.
ii.Glands present in the
intestinal wall produce
intestinal juice.
iii.There is alkaline
medium in the small
intestine.
iv.Food gets completely
digested in the small
intestine.

19. External respiration
Internal respiration
i. External respiration is also
called breathing.
ii. It is a physical process.
iii.It takes place in the
respiratory tract.
iv.The gaseous exchange
between external
atmosphere and the blood
takes place during external
respiration.
v. Oxidation of food does not
occur during external
respiration.
i. Internal respiration is also
called cellular respiration.
ii. It is a biochemical process.
iii.It takes place in the
mitochondria inside the
cell.
iv.The gaseous exchange
between the blood and
tissues occurs during inter
respiration.
v. Oxidation of food occurs
during internal respiration
releasing energy.

20. Arteries
Veins
i. Arteries are blood vessels
which carry blood away from
the heart.
ii. Arteries are thick walled,
elastic blood vessels.
iii.The blood flow in arteries is a
rapid and is under higher
blood pressure.
iv.Arteries are situated deep
inside the body.
v. Arteries do not have valves.
vi.Except for pulmonary artery
all the arteries carry
oxygenated blood.
i. Veins are blood vessels which
carry blood towards the
heart.
ii. Veins are thin walled blood
vessels.
iii.The blood flow in veins is
slower and is under lesser
blood pressure.
iv.Veins are situated
superficially (Apparently) in
the body.
v. Veins have valves to prevent
back flow of the blood.
vi.Except for pulmonary vein all
the veins carry deoxygenated
blood.

21. Atria
Ventricles
i. Atria are the upper
chambers of the heart.
ii. Atria are receiving
chambers as they receive
the blood.
iii.Atria have comparatively
thinner walls.
iv.Superior and inferior vena
cavae enter into right
atrium.
v. Pulmonary veins enter into
the left atrium.
i. Ventricles are the lower
chambers of the heart.
ii. Ventricles are driving
chambers as they sent the
blood the body.
iii.Ventricles have
comparatively thicker
walls.
iv.Pulmonary artery leaves
from right ventricle.
v. Aorta leaves from the left
ventricle.

22. Growth dependent
movements in plants
i. Growth dependent
movements result in the
growth of plants.
ii. Growth dependent
movements are also called
tropic movements.
iii.Growth dependent
movements are in response
to light, water, chemical
stimuli, gravity, etc.
Growth independent
movements in plant.
i. Growth independent
movements do not result in
the growth of plants.
ii. Growth independent
movements are also called
nastic movements.
iii.Growth independent
movements are in response
to touch or for capturing
prey or liberating the
seeds.

23. Central nervous
system
Peripheral nervous
system
i. The central nervous
system is located in
the central part of the
body.
ii. It is composed of
the brain and the
spinal cord.
i. The peripheral
nervous system is
located on the
peripheral parts of the
body.
ii. It is composed of
cranial nerves and
spinal nerves.

24. Cerebrum
cerebellum
i. The cerebrum is the
part of the forebrain.
ii. The cerebrum is
concerned with thinking
and interpreting sensory
information.
iii. The cerebrum stores
memory.
i. The cerebellum is the
part of the hindbrain.
ii. The cerebellum is
concerned with
coordination of voluntary
movements and
maintaining the balance.
iii. The cerebellum does
not store memory.

25. Nervous control in
animal
i. Nervous control of the
body is done with the
help of neurons.
ii.Nervous system is
concerned with the
nervous control.
iii.Nervous impulses are
rapid.
iv.Nervous impulses are
of shorter duration.
Chemical control in
animal
i. Chemical control of the
body is done through
hormones.
ii.Endocrine system is
concerned with the
chemical control.
iii.Hormonal actions are
slower.
iv.Hormonal actions are
of longer duration, i.e.
long lasting.

26. Multiple fission
Regeneration
i. Multiple fission is a
type of asexual
reproduction.
ii. In multiple fission,
division of the nucleus
takes place.
iii. Multiple fission is
carried out by the
repeated division of the
cytoplasm, e.g. Amoeba.
i. Regeneration cannot be
called reproduction
process. It is an
accidental process.
ii. In regeneration
division of the nucleus
may not take place.
iii. Regeneration is
carried out by specialized
cells in the body. e.g.
Planaria.

27. Asexual reproduction
Sexual reproduction
i. Asexual reproduction is the
process in which only one cell
divides into two.
ii. Only one parent participates in
asexual reproduction.
iii. Only mitosis takes place at the
time of asexual reproduction.
iv. The process of fertilization and
formation of zygote do not take
place in asexual reproduction.
v. Somatic cells are involved in the
asexual reproduction.
i. Sexual reproduction is the
process in which two cells fuse
with each other.
ii. Two parents belonging to two
different sexes participate in the
sexual reproduction.
iii. Both mitosis and meiosis take
place at the time of sexual
reproduction.
iv. The process of fertilization and
zygote formation are the
important steps in sexual
reproduction.
v. Germ (Reproductive) cells are
involved in the sexual
reproduction.

28. Mitosis
Meiosis
i. Mitosis is a type of cell division
that takes place in the somatic
cells.
ii. In mitosis the chromosome
number dies not change.
iii. It is also called equational
division as the cells produced
contain the same number of
chromosomes as that of the
parent cell.
iv. Mitosis occurs at the time of
asexual reproduction such as
binary fission. It also takes place
at the time of growth and sexual
reproduction.
i. Meiosis is a type of cell division
that takes place in the germ
cells.
ii. In meiosis the chromosome
number is reproduced to half.
iii. It is also called reduction
division as the cells produced
contain half the number of
chromosomes.
iv. Meiosis occurs at the time of
sexual reproduction during
gamete formation.

29. Testis
Ovary
i. Testis is an essential
gonad in male.
ii.Testis produces
sperms.
iii.Testis secretes
testosterone.
iv.Testis is located
outside the body in the
scrotum.
v. Testis does not have
sperms at the time of
the birth of a boy.
i. Ovary is an essential
gonad in female.
ii.Ovary produces eggs.
iii.Ovary secretes
estrogen.
iv.Ovaries are located
inside the lower
abdomen.
v. Ovary has immature
eggs at the time of the
birth of a girl.

30. Monohybrid cross
Dihybrid cross
i. Crosses involving a
i. Crosses involving two
single pair of alleles are pairs of alleles are
called monohybrid
called dihybrid crosses.
crosses.
ii.Dihybrid crosses yield
ii.Monohybrid crosses
a phenotypic ratio of
yield a phenotypic ratio 9:3:3:1 in the F2
of 3:1 in the F2
generation.
generation.
iii.Genes are assorted to
iii.Genes are not assorted form new combinations
to form new
of characters.
recombination of
characters.

31. Dominant characters
Recessive characters
i. The characters that are
expressed in the F1
generation are called
dominant character.
ii. Tall habit and red colour of
the flower in pea plants are
dominant characters.
iii.Dominant character is
expressed in the presence of
one or both the dominant
genes.
iv.Dominant characters cannot
be masked by recessive
characters.
i. The characters that are not
expressed in the F1
generation are called
recessive characters.
ii. Dwarf habit and white
colour of the flower in pea
plants are recessive
characters.
iii.Recessive characters is
expressed only when both
the recessive alleles of a
gene are present.
iv.Recessive characters can be
masked by dominant
characters.

32. Phenotype
Genotype
i. Phenotype refers to the
outward appearance of an
individual such as shape,
colour, sex, etc.
ii. Phenotype can be observed
directly in an individual.
iii.Individuals resembling
each other may or may not
have the same genotype.
iv.The phenotypic ratio
obtained in the F2
generation of a
monohybrid cross is 3:1.
i. Genotype refers to the
genetic composition of an
individual.
ii. Genotype can be
determined from ancestry
of an individual.
iii.Individuals possessing the
same genotype usually
have the same phenotypic
expression.
iv.The genotypic ratio
obtained in the F2
generation of a
monohybrid cross is 1:2:1.

33. Homologous organs
Analogous organs
i. Homologous organs show
same structural plan.
ii. Functions performed by
the homologous organs are
different.
iii. Homologous organs
explain the common ancestry
in the evolution.
iv. Forelimb of a man, front
leg of a bull, wing of a bird,
fin of a whale are all
homologous organs.
1. Analogous organs show
different structure in
different animals.
ii. Functions performed by
the analogous organs are
always the same.
iii. analogous organs explain
the common adaptation due
to common habitats.
iv. Wing of a bird and wing of
an insect, tail fin of a lobster
and tail flukes of whale are
analogous organs.

34. Sucrose (Sugar)
Water
Glucose (Fructose)
Iron
Sulphur
Iron Sulphide
Carbon dioxide
Carbonic acid
Tricalcium Aluminate
Concrete
Plaster of Paris
Gypsum
Carbon (Coke)
Calcium Carbonate
Copper Sulphate
Zinc
Copper chloride
Silver Bromide
Potassium iodide
C12H22O11
H2O
C6H12O6
Fe
S
FeS
CO2
H2CO3
3CaO.Al2O3
CaO.Al2O36H2O
CaSO4.H2O
CaSO4.2H2O
C
CaCO3
CuSO4
Zn
CuCl2
AgBr
KI

35. Cupric iodide
Potassium Chloride
Potassium chromate
Barium sulphate
Precipitate (yellow)
Potassium Sulphate
Quicklime
Zinc Sulphate
Aluminium
Aluminium Oxide (Alumina)
Ethyl alcohol
Sodium ethoxide
Methane
Hydrochloric acid
Magnesium Chloride
Aluminium chloride
Zinc Chloride
Ferrous chloride
Sulphuric Acid
CuI2
KCl
K2CrO4
BaSO4
BaCrO4
K2SO4
CaO
ZnSO4
Al
Al2O3
C2H5OH
C2H5ONa
CH4
HCl
MgCl2
AlCl3
ZnCl2
FeCl2
H2SO4

36. Magnesium Sulphate
MgSO4
Ferrous sulphate
FeSO4
Sodium aluminate
NaAlO2
Aluminium Hydroxide
Al(OH)3
Zinc sulphide
ZnS
Zinc oxide
ZnO
Zinc carbonate
ZnCO3
Carbon monoxide
CO
Magnesium dioxide
MgO2
Manganese dioxide
MnO2
Iron (II) oxide
Fe2O3
Cinnabar
HgS
Mercuric oxide
HgO
Cuprous Sulphide
Cu2S
Cuprous oxide
Cu2O
Nitric Acid
HNO3
Magnesium nitrate
Mg(NO3)2