10th Physics & Chemistry Book Back 1 Mark Question Papers

Secure a perfect score in your objective sections with our comprehensive collection of 10th Physics, Chemistry Book Back 1 Mark Questions. Textbook exercises, including multiple-choice questions (MCQs), fill-in-the-blanks, true/false, and matching type questions, form the foundational scoring zone of any science paper. This page provides a verified, chapter-wise compilation of all book back questions with precise answer keys. Perfect for quick self-assessment, this guide helps you revise essential concepts, formulas, and chemical definitions in just a few minutes.

10th Science • Physics & Chemistry

Book Back 1 Mark Questions (English Medium)

UNIT 1: LAWS OF MOTION

I. Choose the correct answer

1) Inertia of a body depends on
a) weight of the object b) acceleration due to gravity of the planet
c) mass of the object d) Both a & b

2) Impulse is equals to
a) rate of change of momentum b) rate of force and time
c) change of momentum d) rate of change of mass

3) Newton's III law is applicable
a) for a body is at rest b) for a body in motion c) both a & b d) only for bodies with equal masses

4) Plotting a graph for momentum on the Y-axis and time on X-axis, slope of momentum-time graph gives
a) Impulsive force b) Acceleration c) Force d) Rate of force

5) In which of the following sport the turning effect of force used
a) swimming b) tennis c) cycling d) hockey

6) The unit of 'g' is m s^-2. It can be also expressed as
a) cm s^-1 b) N kg^-1 c) N m² kg^-1 d) cm² s^-1

7) One kilogram force equals to
a) 9.8 dyne b) 9.8 × 10⁴ N c) 98 × 10⁴ dyne d) 980 dyne

8) The mass of a body is measured on planet Earth as M kg. When it is taken to a planet of radius half that of the Earth then its value will be _______ kg.
a) 4 M b) 2 M c) M/4 d) M

9) If the Earth shrinks to 50% of its real radius its mass remaining the same, the weight of a body on the Earth will
a) decrease by 50% b) increase by 50% c) decrease by 25% d) increase by 300%

10) To project the rockets which of the following principle(s) is (are) required?
a) Newton's third law of motion b) Newton's law of gravitation
c) law of conservation of linear momentum d) both a and c

II. Fill in the blanks

1. To produce a displacement _______ is required.

2. Passengers lean forward when sudden brake is applied in a moving vehicle. This can be explained by _______.

3. By convention, the clockwise moments are taken as _______ and the anticlockwise moments are taken as _______.

4. _______ is used to change the speed of car.

5. A man of mass 100 kg has a weight of _______ at the surface of the Earth.

III. State whether the following statements are true or false.

1. The linear momentum of a system of particles is always conserved.

2. Apparent weight of a person is always equal to his actual weight.

3. Weight of a body is greater at the equator and less at the polar region.

4. Turning a nut with a spanner having a short handle is so easy than one with a long handle.

5. There is no gravity in the orbiting space station around the Earth. So the astronauts feel weightlessness.

IV. Match the following

a. Newton's I law	propulsion of a rocket
b. Newton's II law	Stable equilibrium of a body
c. Newton's III law	Law of force
d. Law of conservation of Linear momentum	Flying nature of bird

V. Assertion & Reasoning

Mark the correct choice as:
(a) If both the assertion and the reason are true and the reason is the correct explanation of assertion.
(b) If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
(c) Assertion is true, but the reason is false.
(d) Assertion is false, but the reason is true.

1. Assertion: The sum of the clockwise moments is equal to the sum of the anticlockwise moments.
Reason: The principle of conservation of momentum is valid if the external force on the system is zero.

2. Assertion: The value of 'g' decreases as height and depth increases from the surface of the Earth.
Reason: 'g' depends on the mass of the object and the Earth.

UNIT 2: LIGHT

I. Choose the correct answer.

1. The refractive index of four substances A, B, C and D are 1.31, 1.43, 1.33, 2.4 respectively. The speed of light is maximum in
a) A b) B c) C d) D

2. Where should an object be placed so that a real and inverted image of same size is obtained by a convex lens
a) f b) 2f c) Infinity d) between f and 2f

3. A small bulb is placed at the principal focus of a convex lens. When the bulb is switched on, the lens will produce
a) A convergent beam of light b) A divergent beam of light
c) A parallel beam of light d) A coloured beam of light

4. Magnification of a convex lens is
a) Positive b) negative c) Either positive or negative d) zero

5. A convex lens forms a real, diminished point sized image at focus. Then the position of the object is at
a) Focus b) infinity c) At 2f d) between f and 2f

6. Power of a lens is -4D, then its focal length is
a) 4m b) -40m c) -0.25 m d) -2.5 m

7. In a myopic eye, the image of the object is formed
a) Behind the retina b) on the retina c) In front of the retina d) on the blind spot

8. The eye defect 'presbyopia' can be corrected by
a) Convex lens b) concave lens c) Convex mirror d) Bi focal lenses

9. Which of the following lens would you prefer to use while reading small letters found in dictionary?
a) A convex lens of focal length 5 cm b) A concave lens of focal length 5 cm
c) A convex lens of focal length 10 cm d) A concave lens of focal length 10 cm

10. If V_B, V_G, V_R be the velocity of blue, green and red light respectively in a glass prism, then which of the following statement gives the correct relation?
a) V_B = V_G = V_R b) V_B > V_G > V_R c) V_B < V_G < V_R d) V_B < V_G > V_R

II. Fill in the blanks:

1. The path of the light is called as _______.

2. The refractive index of a transparent medium is always greater than _______.

3. If the energy of incident beam and the scattered beam are same, then the scattering of light is called as _______ scattering.

4. According to Rayleigh's scattering law, the amount of scattering of light is inversely proportional to the fourth power of its _______.

5. Amount of light entering into the eye is controlled by _______.

III. True or False. If false correct it.

1. Velocity of light is greater in denser medium than in rarer medium.

2. The power of lens depends on the focal length of the lens.

3. Increase in the converging power of eye lens causes 'hypermetropia'.

4. The convex lens always gives small virtual image.

IV. Match the following

1. Retina	a. Pathway of light
2. Pupil	b. Far point comes closer
3. Ciliary muscles	c. Near point moves away
4. Myopia	d. Screen of the eye
5. Hypermetropia	e. Power of accommodation

V. Assertion and reasoning

Mark the correct choice as:
a) If both assertion and reason are true and reason is the correct explanation of assertion.
b) If both assertion and reason are true but reason is not the correct explanation of assertion.
c) Assertion is true but reason is false.
d) Assertion is false but reason is true.

1. Assertion: If the refractive index of the medium is high (denser medium) the velocity of light in that medium will be small.
Reason: Refractive index of the medium is inversely proportional to the velocity of light.

2. Assertion: Myopia is due to the increase in the converging power of eye lens.
Reason: Myopia can be corrected with the help of concave lens.

UNIT 3: THERMAL PHYSICS

I. Choose the correct answer.

1. The value of universal gas constant
a) 3.81 J mol^-1 K^-1 b) 8.03 J mol^-1 K^-1 c) 1.38 J mol^-1 K^-1 d) 8.31 J mol^-1 K^-1

2. If a substance is heated or cooled, the change in mass of that substance is
a) Positive b) negative c) Zero d) none of the above

3. If a substance is heated or cooled, the linear expansion occurs along the axis of
a) X or -X b) Y or -Y c) Both (a) and (b) d) (a) or (b)

4. Temperature is the average _______ of the molecules of a substance
a) Difference in K.E and P.E b) Sum of P.E and K.E
c) Difference in T.E and P.E d) Difference in K.E and T.E

5. In the given diagram, the possible direction of heat energy transformation is [Refer diagram in textbook]

II. Fill in the blanks:

1. The value of Avogadro number _______.

2. The temperature and heat are _______ quantities.

3. One calorie is the amount of heat energy required to raise the temperature of _______ of water through _______.

4. According to Boyle's law, the shape of the graph between pressure and reciprocal of volume is _______.

III. State whether the following statements are true or false, if false explain why?

1. For a given heat in liquid, the apparent expansion is more than that of real expansion.

2. Thermal energy always flows from a system at higher temperature to a system at lower temperature.

3. According to Charles's law, at constant pressure, the temperature is inversely proportional to volume.

IV. Match the items in column-I to the items in column-II

1. Linear expansion	(a) change in volume
2. Superficial expansion	(b) hot body to cold body
3. Cubical expansion	(c) 1.381 × 10^-23 J K^-1
4. Heat transformation	(d) change in length
5. Boltzmann constant	(e) change in area

V. Assertion and reason type questions

Mark the correct choice as:
a. Both the assertion and the reason are true and the reason is the correct explanation of the assertion.
b. Both the assertion and the reason are true but the reason is not the correct explanation of the assertion.
c. Assertion is true but the reason is false.
d. Assertion is false but the reason is true.

1. Assertion: There is no effect on other end when one end of the rod is only heated.
Reason: Heat always flows from a region of lower temperature to higher temperature of the rod.

2. Assertion: Gas is highly compressible than solid and liquid.
Reason: Interatomic or intermolecular distance in gas is comparably high.

UNIT 4: ELECTRICITY

I. Choose the best answer

1. Which of the following is correct?
a) Rate of change of charge is electrical power. b) Rate of change of charge is current.
c) Rate of change of energy is current. d) Rate of change of current is charge.

2. SI unit of resistance is
a) Mho b) joule c) Ohm d) ohm meter

3. In a simple circuit, why does the bulb glow when you close the switch?
a) The switch produces electricity. b) Closing the switch completes the circuit.
c) Closing the switch breaks the circuit. d) The bulb is getting charged.

4. Kilowatt hour is the unit of
a) Resistivity b) conductivity c) Electrical energy d) electrical power

II. Fill in the blanks

1. When a circuit is open, _______ cannot pass through it.

2. The ratio of the potential difference to the current is known as _______.

3. The wiring in a house consists of _______ circuits.

4. The power of an electric device is a product of _______ and _______.

5. LED stands for _______.

III. State whether the following statements are true or false: If false correct the statement.

1. Ohm's law states the relationship between power and voltage.

2. MCB is used to protect household electrical appliances.

3. The SI unit for electric current is the Coulomb.

4. One unit of electrical energy consumed is equal to 1000 kilowatt hour.

5. The effective resistance of three resistors connected in series is lesser than the lowest of the individual resistances.

IV. Match the items in column-I to the items in column-II:

Electric current	(a) volt
Potential difference	(b) ohm meter
Specific resistance	(c) watt
Electrical power	(d) joule
Electrical energy	(e) ampere

V. Assertion and reason type questions:

Mark the correct choice as:
a. If both the assertion and the reason are true and the reason is the correct explanation of the assertion.
b. If both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
c. If the assertion is true, but the reason is false.
d. If the assertion is false, but the reason is true.

1. Assertion: Electric appliances with a metallic body have three wire connections.
Reason: Three pin connections reduce heating of the connecting wires.

2. Assertion: In a simple battery circuit the point of highest potential is the positive terminal of the battery.
Reason: The current flows towards the point of the highest potential.

3. Assertion: LED bulbs are far better than incandescent bulbs.
Reason: LED bulbs consume less power than incandescent bulbs.

UNIT 5: ACOUSTICS

I. Choose the correct answer.

1. When a sound wave travels through air, the air particles
a. Vibrate along the direction of wave motion b. Vibrate but not in any fixed direction
c. Vibrate perpendicular to the direction of wave motion d. Do not vibrate

2. Velocity of sound in a gaseous medium is 330 ms^-1. If the pressure is increased by 4 times without causing a change in the temperature, the velocity of sound in the gas is
a) 330 ms^-1 b) 660 ms^-1 c) 156 ms^-1 d) 990 ms^-1

3. The frequency, which is audible to the human ear is
a) 50 kHz b) 20 kHz c) 15000 kHz d) 10000 kHz

4. The velocity of sound in air at a particular temperature is 330 ms^-1. What will be its value when temperature is doubled and the pressure is halved?
a) 330 ms^-1 b) 165 ms^-1 c) 330 × √2 ms^-1 d) 320 / √2 ms^-1

5. If a sound wave travels with a frequency of 1.25 × 10⁴ Hz at 344 ms^-1, the wavelength will be
a) 27.52 m b) 275.2 m c) 0.02752 m d) 2.752 m

6. The sound waves are reflected from an obstacle into the same medium from which they were incident. Which of the following changes?
a) Speed b) frequency c) Wavelength d) none of these

7. Velocity of sound in the atmosphere of a planet is 500 ms^-1. The minimum distance between the sources of sound and the obstacle to hear the echo, should be
a) 17 m b) 20 m c) 25 m d) 50 m

II. Fill up the blanks

1. Rapid back and forth motion of a particle about its mean position is called _______.

2. If the energy in a longitudinal wave travels from south to north, the particles of the medium would be vibrating in _______.

3. A whistle giving out a sound of frequency 450 Hz, approaches a stationary observer at a speed of 33 ms^-1. The frequency heard by the observer is _______ (speed of sound = 330 ms^-1).

4. A source of sound is travelling with a velocity 40 km/h towards an observer and emits a sound of frequency 2000 Hz. If the velocity of sound is 1220 km/h then the apparent frequency heard by the observer is _______.

III. True or false:- (If false give the reason)

1. Sound can travel through solids, gases, liquids and even vacuum.

2. Waves created by Earth Quake are Infrasonic.

3. The velocity of sound is independent of temperature.

4. The velocity of sound is high in gases than liquids.

IV. Match the following

1. Infrasonic	(a) Compressions
2. Echo	(b) 22 kHz
3. Ultrasonic	(c) 10 Hz
4. High pressure Region	(d) Ultrasonography

V. Assertion and Reason Questions

Mark the correct choice as:
a. If both the assertion and the reason are true and the reason is the correct explanation of the assertion.
b. If both the assertion and the reason are true but the reason is not the correct explanation of the assertion.
c. Assertion is true, but the reason is false.
d. Assertion is false, but the reason is true.

1. Assertion: The change in air pressure affects the speed of sound.
Reason: The speed of sound in a gas is proportional to the square of the pressure.

2. Assertion: Sound travels faster in solids than in gases.
Reason: Solids possess a greater density than that of gases.

UNIT 6: NUCLEAR PHYSICS

I. Choose the correct answer

1. Man-made radioactivity is also known as
a. Induced radioactivity b. Spontaneous radioactivity c. Artificial radioactivity d. a & c

2. Unit of radioactivity is
a. Roentgen b. curie c. Becquerel d. all the above

3. Artificial radioactivity was discovered by
a. Becquerel b. Irene Curie c. Roentgen d. Neils Bohr

4. In which of the following, no change in mass number of the daughter nuclei takes place
(i) α decay (ii) β decay (iii) γ decay (iv) neutron decay
a. (i) is correct b. (ii) and (iii) are correct c. (i) & (iv) are correct d. (ii) & (iv) are correct

5. _______ isotope is used for the treatment of cancer.
a. Radio Iodine b. Radio Cobalt c. Radio Carbon d. Radio Nickel

6. Gamma radiations are dangerous because
a. It affects eyes & bones b. It affects tissues
c. It produces genetic disorder d. It produces enormous amount of heat

7. _______ aprons are used to protect us from gamma radiations
a. Lead oxide b. Iron c. Lead d. Aluminium

8. Which of the following statements is/are correct?
i. α particles are photons.     ii. Penetrating power of γ radiation is very low.
iii. Ionization power is maximum for α rays.     iv. Penetrating power of γ radiation is very high.
a. (i) & (ii) are correct     b. (ii) & (iii) are correct     c. (iv) only correct     d. (iii) & (iv) are correct

9. Proton-Proton chain reaction is an example of
a. Nuclear fission b. α - decay c. Nuclear fusion d. β - decay

10. In the nuclear reaction ₆X¹² →_{(α decay)} _ZY^A, the value of A & Z are
a. 8, 6 b. 8, 4 c. 4, 8 d. cannot be determined with the given data

11. Kamini reactor is located at
a. Kalpakkam b. Koodankulam c. Mumbai d. Rajasthan

12. Which of the following is/are correct?
i. Chain reaction takes place in a nuclear reactor and an atomic bomb.
ii. The chain reaction in a nuclear reactor is controlled.
iii. The chain reaction in a nuclear reactor is not controlled.
iv. No chain reaction takes place in an atom bomb.
a. (i) only correct b. (i) & (ii) are correct c. (iv) only correct d. (iii) & (iv) are correct

II. Fill in the blanks

1. One roentgen is equal to _______ disintegrations per second.

2. Positron is an _______.

3. Anemia can be cured by _______ isotope.

4. Abbreviation of ICRP: _______.

5. _______ is used to measure exposure rate of radiation in humans.

6. _______ has the greatest penetration power.

7. _ZY^A → _Z+1Y^A + X; then, X is _______.

8. _ZY^A → _ZY^A; this reaction is possible in _______ decay.

9. The average energy released in each fusion reaction is about _______ J.

10. Nuclear fusion is possible only at an extremely high temperature of the order of _______ K.

11. The radio isotope of _______ helps to increase the productivity of crops.

12. If the radiation exposure is 100 R, it may cause _______.

III. State whether the following statements are true or false: If false, correct the statement

1. Plutonium-239 is a fissionable material.

2. Elements having atomic number greater than 83 can undergo nuclear fusion.

3. Nuclear fusion is more dangerous than nuclear fission.

4. Natural uranium U-238 is the core fuel used in a nuclear reactor.

5. If a moderator is not present, then a nuclear reactor will behave as an atom bomb.

6. During one nuclear fission on an average, 2 to 3 neutrons are produced.

7. Einstein's theory of mass energy equivalence is used in nuclear fission and fusion.

IV. Match the following

Match I:

BARC	Kalpakkam
India's first atomic power station	Apsara
IGCAR	Mumbai
First nuclear reactor in India	Tarapur

Match II:

Fuel	lead
Moderator	heavy water
Control rods	cadmium rods
Shield	Uranium

Match III:

Soddy Fajan	Natural radioactivity
Irene Curie	Displacement law
Henry Becquerel	Mass energy equivalence
Albert Einstein	Artificial Radioactivity

Match IV:

Uncontrolled fission reaction	Hydrogen Bomb
Fertile material	Nuclear reactor
Controlled fission reaction	Breeder reactor
Fusion reaction	Atom bomb

Match V:

Co-60	Age of fossil
I-131	Function of Heart
Na-24	Leukemia
C-14	Thyroid disease

VI. Use the analogy to fill in the blank

1. Spontaneous process : Natural Radioactivity :: Induced process : _______

2. Nuclear Fusion : Extreme temperature :: Nuclear Fission : _______

3. Increasing crops : Radio phosphorous :: Effective functioning of heart : _______

4. Deflected by electric field : α ray :: Null Deflection : _______

UNIT 7: ATOMS AND MOLECULES

I. Choose the best answer.

1. Which of the following has the smallest mass?
a. 6.023 × 10²³ atoms of He b. 1 atom of He c. 2 g of He d. 1 mole atoms of He

2. Which of the following is a triatomic molecule?
a. Glucose b. Helium c. Carbon dioxide d. Hydrogen

3. The volume occupied by 4.4 g of CO₂ at S.T.P
a. 22.4 litre b. 2.24 litre c. 0.24 litre d. 0.1 litre

4. Mass of 1 mole of Nitrogen atom is
a. 28 amu b. 14 amu c. 28 g d. 14 g

5. Which of the following represents 1 amu?
a. Mass of a C-12 atom b. Mass of a hydrogen atom
c. 1/12th of the mass of a C-12 atom d. Mass of O-16 atom

6. Which of the following statements is incorrect?
a. 12 gram of C-12 contains Avogadro's number of atoms.
b. One mole of oxygen gas contains Avogadro's number of molecules.
c. One mole of hydrogen gas contains Avogadro's number of atoms.
d. One mole of electrons stands for 6.023 × 10²³ electrons.

7. The volume occupied by 1 mole of a diatomic gas at S.T.P is
a. 11.2 litre b. 5.6 litre c. 22.4 litre d. 44.8 litre

8. In the nucleus of ₂₀Ca⁴⁰, there are
a. 20 protons and 40 neutrons b. 20 protons and 20 neutrons
c. 20 protons and 40 electrons d. 40 protons and 20 electrons

9. The gram molecular mass of oxygen molecule is
a. 16 g b. 18 g c. 32 g d. 17 g

10. 1 mole of any substance contains _______ molecules.
a. 6.023 × 10²³ b. 6.023 × 10^-23 c. 3.0115 × 10²³ d. 12.046 × 10²³

II. Fill in the blanks

1. Atoms of different elements having same mass number, but different atomic numbers are called _______.

2. Atoms of different elements having same number of neutrons are called isotones.

3. Atoms of one element can be transmuted into atoms of other elements by _______.

4. The sum of the numbers of protons and neutrons of an atom is called its _______.

5. Relative atomic mass is otherwise known as _______.

6. The average atomic mass of hydrogen is _______ amu.

7. If a molecule is made of similar kind of atoms, then it is called _______ atomic molecule.

8. The number of atoms present in a molecule is called its _______.

9. One mole of any gas occupies _______ litres at S.T.P.

III. Match the following

1. 8 g of O₂	4 moles
2. 4 g of H₂	0.25 moles
3. 52 g of He	2 moles
4. 112 g of N₂	0.5 moles
5. 35.5 g of Cl₂	13 moles

IV. True or False: (If false give the correct statement)

1. Two elements sometimes can form more than one compound.

2. Noble gases are diatomic.

3. 1 mole of Gold and Silver contain same number of atoms.

4. Molar mass of CO₂ is 42g.

V. Assertion and Reason:

Answer using the choices:
i) A and R are correct, R explains A.
ii) A is correct, R is wrong.
iii) A is wrong, R is correct.
iv) A and R are correct, R doesn't explain A.

1. Assertion: The Relative Atomic mass of Aluminium is 27.
Reason: An atom of aluminium is 27 times heavier than 1/12^th of the mass of the C-12 atom.

2. Assertion: The Relative Molecular Mass of Chlorine is 35.5 a.m.u.
Reason: The natural abundance of Chlorine isotopes are not equal.

UNIT 8: PERIODIC CLASSIFICATION OF ELEMENTS

I. Choose the best answer.

1. The number of periods and groups in the Periodic table are
a) 6, 16 b) 7, 17 c) 8, 18 d) 7, 18

2. The basis of modern periodic law is
a) Atomic number b) Atomic mass c) Isotopic mass d) Number of neutrons

3. _______ group contains the members of Halogen family.
a) 17th b) 15th c) 18th d) 16th

4. _______ is a relative periodic property.
a) Atomic radii b) ionic radii c) Electron affinity d) electronegativity

5. Chemical formula of rust is
a) FeO·xH₂O b) FeO₄·xH₂O c) Fe₂O₃·xH₂O d) FeO

6. In the aluminothermic process the role of Al is
a) Oxidizing agent b) Reducing agent c) Hydrogenating agent d) Sulphurising agent

7. The process of coating the surface of metal with a thin layer of zinc is called
a) Painting b) thinning c) Galvanization d) electroplating

8. Which of the following inert gases has 2 electrons in the outermost shell?
a) He b) Ne c) Ar d) Kr

9. Neon shows zero electron affinity due to
a) Stable arrangement of neutrons b) Stable configuration of electrons
c) Reduced size d) Increased density

10. _______ is an important metal to form amalgam.
a) Ag b) Hg c) Mg d) Al

II. Fill in the blanks

1. If the electronegativity difference between two bonded atoms in a molecule is greater than 1.7, the nature of bonding is _______.

2. _______ is the longest period in the periodic table.

3. _______ forms the basis of modern periodic table.

4. If the distance between two Cl atoms in Cl₂ molecule is 1.98 Å, then the radius of Cl atom is _______.

5. Among the given species A^-, A⁺, and A, the smallest one in size is _______.

6. The scientist who propounded the modern periodic law is _______.

7. Across the period, ionic radii _______ (increases / decreases).

8. _______ and _______ are called inner transition elements.

9. The chief ore of Aluminium is _______.

10. The chemical name of rust is _______.

III. Match the following

1. Galvanisation	Noble gas elements
2. Calcination	Coating with Zn
3. Redox reaction	Silver-tin amalgam
4. Dental filling	Aluminothermic Process
5. Group 18 Elements	Heating in the absence of air

IV. True or False: (If false give the correct statement)

1. Moseley's periodic table is based on atomic mass.

2. Ionic radius increases across the period from left to right.

3. All ores are minerals; but all minerals cannot be called as ores.

4. Al wires are used as electric cables due to their silvery white colour.

5. An alloy is a heterogeneous mixture of metals.

V. Assertion and Reason

Answer using the choices:
i) A and R are correct, R explains A.
ii) A is correct, R is wrong.
iii) A is wrong, R is correct.
iv) A and R are correct, R doesn't explain A.

1. Assertion: The nature of bond in HF molecule is ionic.
Reason: The electronegativity difference between H and F is 1.9.

2. Assertion: Magnesium is used to protect steel from rusting.
Reason: Magnesium is more reactive than Iron.

3. Assertion: An uncleaned copper vessel is covered with greenish layer.
Reason: Copper is not attacked by alkali.

UNIT 9: SOLUTIONS

I. Choose the correct answer.

1. A solution is a _______ mixture.
a. Homogeneous b. heterogeneous c. Homogeneous and heterogeneous d. Non homogeneous

2. The number of components in a binary solution is
a. 2 b. 3 c. 4 d. 5

3. Which of the following is the universal solvent?
a. Acetone b. Benzene c. Water d. Alcohol

4. A solution in which no more solute can be dissolved in a definite amount of solvent at a given temperature is called
a. Saturated solution b. Unsaturated solution c. Super saturated solution d. Dilute solution

5. Identify the non-aqueous solution.
a. Sodium chloride in water b. Glucose in water
c. Copper sulphate in water d. Sulphur in carbon-di-sulphide

6. When pressure is increased at constant temperature the solubility of gases in liquid
a. No change b. increases c. Decreases d. no reaction

7. Solubility of NaCl in 100 ml water is 36 g. If 25 g of salt is dissolved in 100 ml of water how much more salt is required for saturation?
a. 12 g b. 11 g c. 16 g d. 20 g

8. A 25% alcohol solution means
a. 25 ml alcohol in 100 ml of water b. 25 ml alcohol in 25 ml of water
c. 25 ml alcohol in 75 ml of water d. 75 ml alcohol in 25 ml of water

9. Deliquescence is due to
a. Strong affinity to water b. Less affinity to water c. Strong hatred to water d. Inertness to water

10. Which of the following is hygroscopic in nature?
a. Ferric chloride b. Copper sulphate pentahydrate c. Silica gel d. None of the above

II. Fill in the blanks

1. The component present in lesser amount in a solution is called _______.

2. Example for liquid in solid type solution is _______.

3. Solubility is the amount of solute dissolved in _______ g of solvent.

4. Polar compounds are soluble in _______ solvents.

5. Volume percentage decreases with increases in temperature because _______.

III. Match the following

1. Blue vitriol	CaSO₄·2H₂O
2. Gypsum	CaO
3. Deliquescence	CuSO₄·5H₂O
4. Hygroscopic	NaOH

IV. True or False: (If false give the correct statement)

1. Solutions which contain three components are called binary solution.

2. In a solution the component which is present in lesser amount is called solvent.

3. Sodium chloride dissolved in water forms a non-aqueous solution.

4. The molecular formula of green vitriol is MgSO₄·7H₂O.

5. When Silica gel is kept open, it absorbs moisture from the air, because it is hygroscopic in nature.

UNIT 10: TYPES OF CHEMICAL REACTIONS

I. Choose the correct answer.

1. H_2(g) + Cl_2(g) → 2HCl_(g) is a
a. Decomposition Reaction b. Combination Reaction
c. Single Displacement Reaction d. Double Displacement Reaction

2. Photolysis is a decomposition reaction caused by _______.

3. A reaction between carbon and oxygen is represented by C_(s) + O_2(g) → CO_2(g) + Heat. In which of the type(s), the above reaction can be classified?
i. Combination Reaction ii. Combustion Reaction iii. Decomposition Reaction iv. Irreversible Reaction
a. i and ii b. i and iv c. i, ii and iii d. i, ii and iv

4. The chemical equation Na₂SO_4(aq) + BaCl_2(aq) → BaSO_4(s)↓ + 2NaCl_(aq) represents which of the following types of reaction?
a. Neutralisation b. Combustion c. Precipitation d. Single displacement

5. Which of the following statements are correct about a chemical equilibrium?
(i) It is dynamic in nature.
(ii) The rate of the forward and backward reactions are equal at equilibrium.
(iii) Irreversible reactions do not attain chemical equilibrium.
(iv) The concentration of reactants and products may be different.
a. i, ii and iii b. i, ii and iv c. ii, iii and iv d. i, iii and iv

6. A single displacement reaction is represented by X_(s) + 2HCl_(aq) → XCl_2(aq) + H_2(g). Which of the following(s) could be X: (i) Zn (ii) Ag (iii) Cu (iv) Mg. Choose the best pair.
a. i and ii b. ii and iii c. iii and iv d. i and iv

7. Which of the following is not an "element + element → compound" type reaction?
a. C_(s) + O_2(g) → CO_2(g) b. 2K_(s) + Br_2(l) → 2KBr_(s)
c. 2CO_(g) + O_2(g) → 2CO_2(g) d. 4Fe_(s) + 3O_2(g) → 2Fe₂O_3(s)

8. Which of the following represents a precipitation reaction?
a. A_(s) + B_(s) → C_(s) + D_(s) b. A_(s) + B_(aq) → C_(aq) + D_(l)
c. A_(aq) + B_(aq) → C_(s) + D_(aq) d. A_(aq) + B_(s) → C_(aq) + D_(l)

9. The pH of a solution is 3. Its [OH^-] concentration is
a. 1 × 10^-3 M b. 3 M c. 1 × 10^-11 M d. 11 M

10. Powdered CaCO₃ reacts more rapidly than flaky CaCO₃ because of
a. Large surface area b. High pressure c. High concentration d. High temperature

II. Fill in the blanks

1. A reaction between an acid and a base is called _______.

2. When lithium metal is placed in hydrochloric acid, _______ gas is evolved.

3. The equilibrium attained during the melting of ice is known as _______.

4. The pH of a fruit juice is 5.6. If you add slaked lime to this juice, its pH _______ (increases / decreases).

5. The value of ionic product of water at 25°C is _______.

6. The normal pH of human blood is _______.

7. Electrolysis is a type of _______ reaction.

8. The number of products formed in a synthesis reaction is _______.

9. Chemical volcano is an example for _______.

10. The ion formed by dissolution of H⁺ in water is called _______.

III. Match the following (Identify the types of reaction):

REACTION	TYPE OF REACTION
NH₄OH_(aq) + CH₃COOH_(aq) → CH₃COONH_4(aq) + H₂O_(l)	Single Displacement
Zn_(s) + CuSO_4(aq) → ZnSO_4(aq) + Cu_(s)	Combustion
ZnCO_3(s) + Heat → ZnO_(s) + CO_2(g)	Neutralisation
C₂H_4(g) + 4O_2(g) → 2CO_2(g) + 2H₂O_(g) + Heat	Thermal decomposition

IV. True or False: (If false give the correct statement)

1. Silver metal can displace hydrogen gas from nitric acid.

2. The pH of rain water containing dissolved gases like SO₃, CO₂, NO₂ will be less than 7.

3. At the equilibrium of a reversible reaction, the concentration of the reactants and the products will be equal.

4. Periodical removal of one of the products of a reversible reaction increases the yield.

5. On dipping a pH paper in a solution, it turns into yellow. Then the solution is basic.

UNIT 11: CARBON AND ITS COMPOUNDS

I. Choose the best answer.

1. The molecular formula of an open chain organic compound is C₂H₆. The class of the compound is
a. Alkane b. alkene c. Alkyne d. alcohol

2. The IUPAC name of an organic compound is 3-Methyl butan-1-ol. What type compound it is?
a. Aldehyde b. Carboxylic acid c. Ketone d. Alcohol

3. The secondary suffix used in IUPAC nomenclature of an aldehyde is
a. -ol b. -oic acid c. -al d. -one

4. Which of the following pairs can be the successive members of a homologous series?
a. C₃H₈ and C₄H₁₀ b. C₂H₂ and C₂H₄
c. CH₄ and C₃H₆ d. C₂H₅OH and C₄H₉OH

5. C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O is a
a. Reduction of ethanol b. Combustion of ethanol
c. Oxidation of ethanoic acid d. Oxidation of ethanal

6. Rectified spirit is an aqueous solution which contains about _______ of ethanol.
a. 95.5% b. 75.5% c. 55.5% d. 45.5%

7. Which of the following are used as anaesthetics?
a. Carboxylic acids b. Ethers c. Esters d. Aldehydes

8. TFM in soaps represents _______ content in soap.
a. Mineral b. vitamin c. Fatty acid d. carbohydrate

9. Which of the following statements is wrong about detergents?
a. It is a sodium salt of long chain fatty acids.
b. It is sodium salts of sulphonic acids.
c. The ionic part in a detergent is −SO₃⁻Na⁺.
d. It is effective even in hard water.

II. Fill in the blanks

1. An atom or a group of atoms which is responsible for chemical characteristics of an organic compound is called _______.

2. The general molecular formula of alkynes is _______.

3. In IUPAC name, the carbon skeleton of a compound is represented by _______ (root word / prefix / suffix).

4. _______ (Saturated / Unsaturated) compounds decolourise bromine water.

5. Dehydration of ethanol by conc. sulphuric acid forms _______ (ethene / ethane).

6. 100% pure ethanol is called _______.

7. Ethanoic acid turns _______ litmus to _______.

8. The alkaline hydrolysis of fatty acids is termed as _______.

9. Biodegradable detergents are made of _______ (branched / straight) chain hydrocarbons.

III. Match the following

Functional group -OH	Benzene
Heterocyclic	Potassium stearate
Unsaturated	Alcohol
Soap	Furan
Carbocyclic	Ethene

IV. Assertion and Reason:

Answer using the choices:
i) A and R are correct, R explains A.
ii) A is correct, R is wrong.
iii) A is wrong, R is correct.
iv) A and R are correct, R doesn't explain A.

1. Assertion: Detergents are more effective cleansing agents than soaps in hard water.
Reason: Calcium and magnesium salts of detergents are water soluble.

2. Assertion: Alkanes are saturated hydrocarbons.
Reason: Hydrocarbons consist of covalent bonds.