Monthly Archives: May 2023

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

i.) Assertion: A bisexual flower produces ova as well as pollen.

Reason: Ova and pollen are produced in the carpel.

Answer – (c) A is true but R is false

ii) Assertion: Female produces two types of gametes.

Reason: Female has two X chromosomes..

Answer – (d) A is false but R is true

iii) Assertion: Height in pea plants is controlled by efficiency of enzymes and is thus genetically controlled.

Reason: Cellular DNA is the information source for making proteins in the cell.

Answer: (a) Both A and R are true and R is the correct explanation of A

IV) Assertion (A): Offsprings produced by sexual reproduction show variation.

Reason (R): Each offspring produced by sexual reproduction inherits all the genes from
each parent.

Answer: C. A is true, but R is false

5) Assertion: Probability of survival of an organism produced through sexual reproduction is more than that of organism produced through asexual mode.

Reason: Variations provide advantages to individuals for survival.

Answer: a) Both A and R are true and R is the correct explanation of A

Q.1. Assertion(A) : Asexual reproduction is a primitive type of reproduction.
Reason (R) : Asexual reproduction involves only mitotic cell division.

Answer(a)

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Q.2. Assertion(A) : Spores are unicellular bodies.
Reason (R) : The parent body simply breaks up into smaller pieces on maturation.

Answer(c)

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Q.3. Assertion(A) : Clones are offspring of an organism formed by asexual reproduction.
Reason (R) : Clones have exact copies of DNA as their parent.

Answer(b)

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Q.4. Assertion(A) : Colonies of yeast multiply in sugar solution.
Reason (R) : Sugar is made of sucrose which provides energy for sustaining all life activities.

Answer(a)

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Q.5. Assertion(A): Pollen grains from the carpel stick to the stigma of stamen.
Reason (R) : The fertilised egg cells grow inside the ovules and become seeds.

Answer(d)

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Q.6. Assertion(A) : The offspring produced by sexual reproduction is likely to adjust better in environmental fluctuation.
Reason (R) : During the fusion of gametes there is mixing of genetic material from two parents.

Answer(a)

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Q.7. Assertion(A) : Growth hormone stimulates the growth of different body parts.
Reason (R) : Gonadotropins stimulate the production of sex hormones.

Answer (B)

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Q.8. Assertion(A): Testes lie in penis outside the body.
Reason (R) : Sperms require temperature lower than the body temperature for development

Answer(d)

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Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

Q.1. Assertion(A) : Insulin regulates blood sugar level.
Reason (R) : Insufficient secretion of insulin will cause diabetes.

Answer(a)

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Q.2. Assertion(A) : Animals can react to stimuli in different ways.
Reason (R) : All animals have a nervous system and an endocrine system involving hormones.

Answer(a)

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Q.3. Assertion(A): The effect of auxin hormone on the growth of root is exactly opposite to that on a stem.
Reason (R) : Auxin hormone increases the rate of growth in root and decreases the rate of growth in stem.

Answer(c)

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Q.4. Assertion(A): A receptor is a specialized group of cells in a sense organ that perceive a particular type of stimulus.
Reason (R) : Different sense organs have different receptors for detecting stimuli.

Answer(b)

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Q.5. Assertion(A): Cyton region of nerve fibre collects information for the brain.
Reason (R): Nerve fibres can either have or lack myelin sheath.

Answer(d)

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Q.6. Assertion(A): A nerve impulse is an electrochemical event.
Reason (R) : In a nerve impulse there are changes in the resting potential which spreads down the nerve fibre.

Answer(a)

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Q.7. Assertion(A) : The brain is also known as the central nervous system.
Reason (R) : Central nervous system controls and regulates the voluntary actions.

Answer(d)

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Q.8. Assertion(A) : The spinal nerves are 31 in number.
Reason (R) : Spinal nerves only have sensory neurons in them

Answer(c)

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Q.9. Assertion (A) : Insulin regulates blood sugar level.

Reason (R) : Insufficient secretion of insulin will cause diabetes.

Answer (A)

Q.10. Assertion(A): A growing plant appears to bend towards the direction of light

Reason (R) : The plant hormone auxin diffuses towards the shady side of the root.

Answer (A)

Q.11. Assertion (A) : The effect of auxin hormone on the growth of root is exactly opposite to that on a stem.

Reason (R) : Auxin hormone increases the rate of growth in root and decreases the rate of growth in stem.

Answer (C)

Q.12. Assertion(A) : The use of iodised salt prevents risk of goitre.

Reason (R) : Iodised salt provides iodine needed by thyroid gland to make sufficient thyroxin for our body.

Answer (A)

Q.13. Assertion (A) : The brain is also known as the central nervous system.

Reason (R) : Central nervous system controls and regulates the voluntary actions.

Answer (D)

Q.14. Assertion (A) : Animals can react to stimuli in different ways.

Reason (R) : All animals have a nervous system and an endocrine system involving hormones.

Answer (A)

Q.15. Assertion (A) : A receptor is a specialized group of cells in a sense organ that perceive a particular type of stimulus.

Reason (R) : Different sense organs have different receptors for detecting stimuli.

Answer (B)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

Q.1. Assertion (A) : Plants lack excretory organs.
Reason (R) : Plants usually absorb essential nutrients.

Answer(b)

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Q.2. Assertion (A) : In anaerobic respiration, one of the end product is alcohol.
Reason (R) : There is an incomplete breakdown of glucose.

Answer(a)

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Q.3. Assertion (A) : In plants there is no need of specialised respiratory organs.
Reason (R) : Plants do not have great demands of gaseous exchange.

Answer(a)

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Q.4. Assertion (A) : Bile is essential for digestion of lipids.
Reason (R) : Bile juice contains enzymes.

Answer(c)

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Q.5. Assertion (A) : Carbohydrate digestion mainly takes place in small intestine.
Reason (R) : Pancreatic juice contains the enzyme lactase.

Answer(c)

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Q.6. Assertion (A) : Aerobic respiration requires less energy as compared to anaerobic respiration.
Reason (R) : Mitochondria is the powerhouse of the cell.

Answer(d)

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Q.7. Assertion (A): Arteries are thick-walled and elastic in nature.
Reason (R) : Arteries have to transport blood away from the heart.

Answer(b)

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Q.8. Assertion (A) : Human heart is four-chambered.
Reason (R) : Vena cava is the only artery that supplies deoxygenated blood to the heart.

Answer(c)

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Q.9. Assertion (A): Energy is required to carry out different life processes.
Reason (R) : Energy is obtained in the form of ATP in the mitochondria.

Answer(a)

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Q.10. Assertion (A): Rings of cartilage are present in the throat,
Reason (R) : These ensure that the air-passage does not collapse

Answer(a)

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Q.11. Assertion (A): Pyruvate is a six-carbon molecule
Reason (R) : It is prepared in the cytoplasm as the first step to cellular respiration

Answer(d)

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Q.12. Assertion (A): Molecular movements are needed for life.
Reason (R): Body structures made up of these molecules need continuous repair and maintenance

Answer(a)

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Q.13. Assertion (A): Diffusion does not meet high energy requirements of multi-cellular organisms
Reason (R) : Diffusion is a fast process but occurs at the surface of the body.

Answer(c)

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Q.14. Assertion (A): The opening and closing of the pore is a function of the guard cells.
Reason (R) : Stomatal pores are the site for exchange of gases by diffusion.

Answer(b)

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Q.15. Assertion (A): The purpose of making urine is to filter out undigested food from intestine
Reason (R): Kidneys filter the waste and produce urine,

Answer(d)

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Q.16. Assertion (A): The inner lining of the small intestine has numerous finger-like projections called villi.
Reason (R) : The villi increase the surface area for absorption.

Answer(a)

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Q.17. Assertion (A): In human beings, the respiratory pigment is haemoglobin
Reason (R) : It is a type of protein which has high-affinity carbon dioxide.

Answer(c)

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Q.18. Assertion : The plants store some of the waste products in their body parts.
Reason: Raphides are the solid waste products of plants.

Answer(b)

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Q.19. Assertion : The movement of water and dissolved salts in xylem is always upwards.
Reason: ‘The upward movement of water is due to low pressure created by transpiration.

Answer(a)

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Q.20. Assertion : Photosynthesis takes place in green parts of the plants.
Reason: Photosynthesis always takes place in leaves.

Answer(c)

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Q.21. Assertion: The average number of heart beat of a person at rest is about 80 per minute.
Reason: One contraction and relaxation of the heart constitutes a complete heart beat.

Answer(d)

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Q.22. Assertion : Ureters are the tubes which carry urine from kidneys to the bladder.
Reason: Urine is stored in the urethra.

Answer(c)

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Q.23. Assertion : Ventricles have thicker walls than auricles.
Reason: Ventricles have to pump blood into various organs with great pressure

Answer(a)

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Q.24. Assertion : Capillaries are the thinnest blood vessels.
Reason: Capillaries connect the branches of arteries and veins.

Answer(b)

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Q.25. Assertion : Blood takes up oxygen from the alveolar air and release CO2 during exchange.
Reason: ‘The concentration of O, is more in alveolar air.

Answer(b)

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Q.26. Assertion: The large intestine is the largest part of the alimentary canal.
Reason: Tiger has a shorter small intestine, than herbivores.

Answer(d)

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Q.27. Assertion : Most of the living organisms carry out aerobic respiration.
Reason: Mitochondria is the site of aerobic respiration in the cell.

Answer(b)

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Q.28. Assertion : The Bowman’s capsule and the tubule together make a nephron.
Reason : The function of tubule is to allow the selective reabsorption of substances like glucose, amino
acids, urea, salts and water into the blood capillaries.

Answer(c)

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Q.29. Assertion : Pancreatic juice digests starch, proteins and fats.
Reason: Pancreatic juice contains digestive enzymes like pancreatic amylase, trypsin and lipase.

Answer (a)

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Q.30. Assertion: The accumulation of lactic acid in the muscles causes muscle cramps.
Reason: During vigorous physical exercise leg muscles respire anaerobically.

Answer(a)

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Q.31. Assertion : Phloem helps in translocation of food from the leaves.
Reason: Phloem provides mechanical support to plant.

Answer(c)

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Q.32. Assertion : Trachea does not collapse, when there is no air in it.
Reason : Trachea is supported by cartilage.

Answer(a)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

1.) Assertion: Lithium and Sodium both belong to same group.

Reason: Lithium and sodium both have same atomic number.

Answer – (c) Assertion is true but the Reason is false.

2.) Assertion: K shell of an atom can accommodate maximum 2 electrons.

Reason: K shell is always the outermost shell of an particular atom.

Answer – (c) Assertion is true but the Reason is false.

3.) Assertion: Elements having same number of valence shell are placed in same group.

Reason: In a group metallic character increases from Upper to Lower.

Answer – (b) The Assertion and the Reason are correct but the Reason is not the
correct explanation of the Assertion.

4.) Assertion: In a period as we move from left to right nature of oxides gradually changes from basic to acidic.

Reason: On moving left to right in a period non metallic character increases.

Answer – (a) Both the Assertion and the Reason are correct and the Reason is the
correct explanation of the Assertion.

5.) Assertion: The term atomic size refers to the radius of an atom.

Reason: Atomic size depends on – number of protons present in an atom.

Answer – (c) Assertion is true but the Reason is false.

6) Assertion (A) : Mendeléev concentrated on the compounds formed by elements with oxygen and hydrogen in his periodic table.
Reason (R) : Hydrogen and oxygen are very reactive and form compounds with most elements.

Answer(a)

7)Assertion (A) : In Mendeléev Periodic Table, cobalt was placed before nickel.
Reason (R): The atomic mass of cobalt is less than nickel.

Answer(c)

8) Assertion (A) : According to Mendeléev, the properties of elements are a periodic function of their atomic masses.
Reason (R) : Atomic number is equal to the number of protons.

Answer(b)

9) Assertion (A) : Noble gases have zero valency.
Reason (R) : Noble gases have stable electronic configuration.

Answer(a)

10) Assertion (A) : Elements in the same vertical column have similar properties.
Reason (R) : Elements have periodic dependence upon the atomic number.

Answer(b)

11) Assertion (A) : Silicon is a metalloid.
Reason (R) : Silicon shows only properties of non-metals.

Answer(c)

12) Assertion (A) : Fluorine has greater atomic radius than nitrogen.
Reason (R): Atomic radius decreases along a period.

Answer(d)

13)  Assertion (A): Li, Na, K form Döbereiner’s triads.
Reason (R) : Atomic mass of Na is roughly the average of atomic masses of Li and K.

Answer(a)

14) Assertion (A) : Magnesium belongs to 3rd period of modern periodic table.
Reason (R) : The valence electrons of magnesium is 2.

Answer(b)

15) Assertion (A) : Isotopes are placed together in the modern periodic table.
Reason (R) : Isotopes have same atomic number.

Answer(a)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

1) Assertion: Ethanoic acid liberates hydrogen with Sodium metal.

Reason: More reactive sodium displaces hydrogen from ethanoic acid.

Answer – (a) Both the Assertion and the Reason are correct and the Reason is the
correct explanation of the Assertion.

2) Assertion: Ethanoic acid reacts with ethyl alcohol in presence of conc H2SO4 to form ethyl ethanoate.

Reason: Esters are used in ice creams and cold drinks.’

Answer – (b) The Assertion and the Reason are correct but the Reason is not the
correct explanation of the Assertion.

3) Assertion: Carbon forms a large number of organic compounds.

Reason : Carbon atom contains 6 valence electrons.

Answer – (c) Assertion is true but the Reason is false.

4) Assertion: During the reaction esterification esters are produced.

Reason: Esters are sweet smelling compounds.

Answer – (b) The Assertion and the Reason are correct but the Reason is not the
correct explanation of the Assertion.

5) Assertion: Vegetable oils are unsaturated, react with hydrogen in presence of nickel to form vegetable ghee.

Reason: This reaction is saponification.

Answer – (c) Assertion is true but the Reason is false.

6) Assertion(A) : Carbon is the only element that can form large number of compounds.
Reason (R) : Carbon is tetravalent and shows the property of catenation.

Answer(d)

7) Assertion(A) : If the first member of a homologous series is methanal, its third member will be propanal.
Reason (R) : All the members of a homologous series show similar chemical properties.

Answer(b)

8) Assertion(A) : Diamond and graphite are allotropes of carbon.
Reason (R) : Some elements can have several different structural forms while in the same physical state. These forms are called allotropes.

Answer(a)

9) Assertion(A) : Soaps are not suitable for washing purpose when water is hard.
Reason (R) : Soaps have relatively weak cleansing action.

Answer(b)

10) Assertion(A) : Carbon compounds can form chain, branched and ring structures.
Reason (R) : Carbon exhibits the property of catenation.

Answer(a)

11) Assertion (A) : Carbon monoxide is extremely poisonous in nature.
Reason (R) : Carbon monoxide is formed by complete combustion of carbon.

Answer(c)

12) Q.7. Assertion (A) : Cooking oil decolourises bromine water.
Reason (R) : Cooking oil is a saturated compound.

Answer(b)

13) Assertion (A) : In a candle, wax vapours burn in sufficient supply of oxygen, which leads to blue flame.
Reason (R) : When the oxygen supply is sufficient, then fuels burn completely producing a blue flame.

Answer(a)

14) Assertion (A) : Alkanes give addition reaction.
Reason (R) : Addition reactions are a characteristic property of unsaturated hydrocarbons.

Answer(d)

15) Assertion(A): n-butane and iso-butane are examples of isomers.
Reason (R) : Isomerism is possible only with hydrocarbons having 4 or more carbon atoms.

Answer(b)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

1.Assertion: Bauxite is the most important ore of Aluminium.

     Reason: Carbon is used to reduce bauxite to aluminium

     Answer. (a)

  2.Assertion: Brass is an alloy of Zinc and Magnesium.

     Reason: Alloys are homogenous mixture of two or more metals.

     Answer. (d) 

     The statement of the Assertion is false but the Reason is true.

 3.Assertion: Iron can be obtained from Fe₂O₃ by reduction with aluminium.

     Reason: The process is known as thermite process.

      Answer . (a)

 both assertion and reason are right and it is the correct reason for assertion 

  4.Assertion: Elements Pt, Ag, noble gases, etc. occur in native state in nature.

      Reason: Elements which are attacked by moisture, oxygen and CO₂  of air occur in native state.

       Answer

Assertion is true for given statement while reason is wrong.

  5.Assertion: Reactivity Series is an arrangement of element based on their reactivity.

      Reason: Reactivity Series is used to separate elements based on their reactivity.

Answer. a) both assertion and reason are correct and reason is correct explanation of assertion

 6. Assertion :Metals like Na, K, Ca and Mg are never found in their free state     in nature
Reason :Metals are very reactive elements, so it combines with other non-metals to complete its octet. Metals like Na, K, Ca and Mg are never found in their state in nature.

Answer. (a) Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

7. Assertion: Nitrogen is a non-metal.
Reason: Nitrogen has 5 valence electrons.

Answer: b

The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.

8.Assertion: Al₂O₃, is an amphoteric oxide.
Reason: Al₂O₃ reacts with acid as well as base to form salt and water.

Answer: a
Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

 9.Assertion: Highly reactive metals are obtained by electrolytic reduction of their molten ore.
Reason: Highly reactive metals can be extracted by chemical reduction.

Answer: c
(c) Assertion is true but the Reason is false.

 10.Assertion: Copper does not reacts with the H₂SO₄.
Reason: Copper is more reactive than hydrogen

Answer: c

 Assertion is true but the Reason is false.

 11.Assertion: Silver becomes black in colour when exposed to atmosphere.
Reason: Silver reacts with H^S gas to form Ag,S which is black in colour.

Answer: a
Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.

12. ASSERTION: Isotopes have same atomic masses.
    REASON: Isotopes have same atomic number and have similar chemical properties.

 Answer. (D)

 If assertion is INCORRECT, but reason is CORRECT


13. ASSERTION: Metallic character decreases across a period.
    REASON: Metals are electro-negative.

 Answer. (C)

 If assertion is CORRECT, but reason is INCORRECT



14. ASSERTION: Sodium bicarbonate is used in antacid medicines.
    REASON: It is a mild based which neutralizes the acidity of gastric juice.

Answer.(a)
If both assertion and reason are CORRECT and reason is the CORRECT explanation of the assertion.

 15.ASSERTION: Ethylene is an unsaturated hydrocarbon.
    REASON: Ethylene contains carbon-carbon triple covalent bond.

  Answer. (c )

   If assertion is CORRECT, but reason is INCORRECT

16. ASSERTION: Sodium and potassium is stored under kerosene.
    REASON: Sodium (Na) and Potassium (K) belongs to group IA, so they are alkali metals.

 Answer . (B)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

Q1. Assertion (A): Carbonic Acids is used in making soft drinks.      

Reason (R): All mineral acids are corrosive.  

Answer. (d) 

 Reason is true but Assertion is false. 

Q2. Assertion (A): Lime Juice has a sour taste, while lime water is slightly bitter.  

 Reason (R): The bitter taste of lime water is due to dilution. 

Answer .(a) 

Both assertion and reason are true and reason is  the correct Explanation of assertion 

 Q3. Assertion (A): Antacids are used to get rid of pain caused by indigestion. 

Reason (R): Antacids neutralise the excess acid produced in the stomach. 

   Answer. (b) 

    both Assertion and Reason are true but Reason is not the correct explanation of Assertion 

 Q4. Assertion (A): Tooth decay starts when the pH of the mouth is lower than 5.5. 

Reason (R) : Bee – Sting leaves an acid which causes pain and irritation.  

  Answer (b) 

  both Assertion and Reason are true but Reason is not the correct explanation of Assertion 

Q5. Assertion (A): When pH of rain water is more than 7, it is called acid rain.  

 Reason (R) : When electricity is passed through an aqueous solutions of sodium        chloride, it decomposes to form sodium carbonate 

Answer . (c) 

Assertion is true but Reason is false. 

Q6. Assertion: Acetic acid does not act as an acid in benzene solution.          

Reason: Benzene is non-polar. 

Answer (a) Option1. Both assertion and reason are correct and reason is  the correct Explanation of assertion  

Q7. Assertion: Calcium oxide is a base but not an alkali. 

 Reason: Calcium oxide is insoluble in water. 

Answer (a)  

Both assertion and reason are correct and reason is  the correct Explanation of assertion 

Q8. Assertion: There is no change in the colour of litmus paper when       brought in contact with distilled water. 

Reason: Litmus Paper is used to find whether an solution is Acidic or     Basic. 

Answer (b) 

Both assertion and reason are correct and reason is not the correct  

Q9. Assertion: When bleaching power is left in the open, its colour changes from blue to white. 

Reason: The change in colour as oxygen breaks away from the compound. 

Answer(c) 

Assertion is true, reason is false 

10. Assertion: Sodium and Potassium is kept inside kerosene. 

Reason: Sodium does not react with organic solvents like kerosene. 

Answer (b) 

Both assertion and reason are true and reason is not the correct Explanation of assertion  

Q11. Assertion:   Chemical reaction changes the physical and chemical state of  a substance. 

Reason:  When electric current is passed through water (liquid),  it decomposes to produce hydrogen and oxygen gases. 

Answer(a)  Both assertion and reason are true and reason is  the correct Explanation of assertion  

Q12. Assertion: In a balanced chemical equation, total mass of the each element towards reactant side= total mass of the same element towards product side.

Reason: Mass can neither be created nor destroyed during a chemical change. 

Answer (c) 

Assertion is true but reason is false 

Q13. Assertion: When calcium carbonate is heated, it decomposes to give calcium oxide and carbon dioxide. 

Reason: The decomposition reaction takes place on application of heat, therefore, its and endothermic reaction. 

Answer b) 

 Both assertion and reason are true but reason is not a correct explain the assertion. 

Q14. Assertion: Chips manufacturers usually flush bags of chips with gas such as nitrogen to prevent the chips from getting oxidised. 

Reason: This increase the taste of the chips and helps in their digestion. 

Answer (c) 

Assertion is true but Reason is false. 

Q15. Assertion: Rusting of iron metal is the most common form of corrosion. 

Reason: The effect of rusting of iron can be reversed if they are left open in sunlight. 

Answer (c) assertion is true but reasoning is false 

Q16. Assertion: Iron can be obtained from Fe₂O₃ by reduction   with aluminium.    

  Reason: The process is known as thermite process. 

Answer (a) 

Both Assertion and Reason are true and Reason is the correct explanation of  Assertion.     

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

Q1. Assertion: Magnesium ribbon keeps on burning in atmosphere of nitrogen.
Reason: Magnesium reacts with nitrogen to form magnesium nitrides and this reaction is combination reaction.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (a) Both A and R are true and R is the correct explanation of A.

Q2. Assertion: MnO₂ + 4HCl → MnCl₂ + Cl₂ + 2H₂O is redox reaction.

Reason: MnO₂ oxides HCl to Cl₂ and gets reduced to MnCl.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (a) Both A and R are true and R is the correct explanation of A.

Q3. Assertion: A lead nitrate on thermal decomposition gives lead oxide, brown coloured nitrogen dioxide and oxygen gas.
Reason: Lead nitrate reacts with potassium iodide to form yellow ppt of lead iodide and the reaction is double displacement as well as precipitation reaction.

Answer. (b) Both A and R are true but R is not the correct explanation of A.

Q4. Assertion: Zinc reacts with sulphuric acid to form zinc sulphate and hydrogen gas and it is displacement reaction.
Reason: Zinc reacts with oxygen to form zinc oxide.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (b) Both A and R are true but R is not the correct explanation of A.

Q6. ASSERTION:  Combustion reactions are also called exothermic oxidation reactions.
REASON:  In these reactions, oxygen is added and heat energy is released.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (A) Both assertion and reason are correct and the reason is the CORRECT explanation of the assertion.

Q7. ASSERTION:  Colour of copper sulphate does not change when an iron nail is kept in it.
REASON:   Iron is more reactive than copper and it displaces it.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false

Answer. (D) Assertion is incorrect. Iron is more reactive displaces Cu and forms FeSO₄ which changes the colour.

Q8. ASSERTION:  White silver chloride turns grey in the presence of sunlight.
REASON:    In the presence of the sunlight, silver chloride decomposes into silver metal and chlorine gas.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (A) Both assertion and reason are correct and the reason is the

CORRECT explanation of the assertion.

Q9. ASSERTION: Calcium carbonate on heating breaks into Calcium Oxide and Cabon dioxide gas.
REASON:  Calcium carbonate is a base.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (B) If both assertion and reason are CORRECT, but the reason is NOT THE CORRECT explanation of the assertion.
   CaCO₃ breaks due to thermal decomposition and it is an endothermic reaction.

Q10. ASSERTION:  Rusting of iron is a chemical change.
REASON:  The chemical properties of hydrated iron oxide are different from iron and oxygen.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (A) Both assertion and reason are correct and the reason is the CORRECT explanation of the assertion.

Q11. ASSERTION: The chemical reaction during which hydrogen is lost is called as reduction reaction.
REASON: Reducing agent removes hydrogen.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Answer. (E) If both assertion and reason are INCORRECT

Q12. ASSERTION: Nitrogen is flushed in potato chip packets to preserve acidity of potato chips.
REASON:    Nitrogen prevents contact of chips to air and thus prevents oxidation.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

 Answer. (D) If the assertion is INCORRECT, but the reason is CORRECT
   Nitrogen is flushed to avoid potato chips getting rancid.

Q13. Assertion : Corrosion of iron is commonly known as

rusting.

Reason : Corrosion of iron occurs in presence of water

and air.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (b) If both Assertion and Reason are correct,

but Reason is not the correct explanation of

Assertion.

Corrosion occurs due to oxidation of iron.

Q14. Assertion : In a reaction.

Zn(s) + CuSO4 (aq) 🡪 ZnSO4 (aq) + Cu(s) 

Zn is a reductant but itself get oxidized.

Reason : In a redox reaction, oxidant is reduced by

accepting electrons and reductant is oxidized by losing

electrons.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

Q15. Assertion : A reducing agent is a substance which can

either accept electron.

Reason : A substance which helps in oxidation is

known as reducing agent.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (d) If Assertion is incorrect but Reason is correct

A reducing agent is a substance which oxidizes itself but reduces others i.e., looses electrons.

Q16. Assertion : The balancing of chemical equations is

based on law of conservation of mass.

Reason : Total mass of reactants is equal to total mass

of products.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.

Q17. Assertion (A) : Carbon dioxide turns lime water milky.

Reason (R) : Carbon dioxide sullies the water.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (c) Assertion (A) is true but reason (R) is false. Carbon dioxide reacts with lime water (calcium

hydroxide) to form milky precipitate of calcium carbonate.

Q18. Assertion (A) : A chemical reaction becomes faster at higher temperatures.

Reason (R) : At higher temperatures, molecular motion becomes more rapid.

(a) Both A and R are true and R is the correct explanation of A.

(b) Both A and R are true but R is not the correct explanation of A.

(c) A is true but R is false.

(d) A is false but R is true.

(e) Both A and R are false.

Ans : (a) Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

1.) Assertion: The probability of an event that cannot happen or which is impossible, is equal to zero.

Reason: The probability lies between 0 and 1. Hence, it cannot be negative

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: b) both assertion and  reason are correct but  reason is  not correct explanation for assertion.

2.) Assertion: If P(E) = 0.07, then  its  probability of ‘not E’ is 0.93

Reason : P(E) + P(not E) = 1

Since, P(E) = 0.05

 P(not E) = 1 – P(E)

P(not E) = 1 – 0.07P = 0.93

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: a) both assertion and reason are correct and reason is correct explanation for assertion.

3.) Assertion: . A bag has 3 red balls and 5 green balls. If we take a ball from the bag, then probability of getting red balls only 3/8.

Reason: Probability of getting red balls = number of red balls/total number of balls

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: a) both assertion and reason are correct and reason is correct explanation for assertion.

4.) Assertion: The sum of the probabilities of all the elementary events of an experiment is 1.

Reason: If an event cannot occur, then its probability is 0.

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

5.) Assertion: The probability of getting a bad egg in a lot of 400 is 0.035. The number of bad eggs in the lot is 14.

Reason: . If the probability of an event is p, the probability of its complementary event will be 1-p.

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

6.) Assertion: The probability of getting exactly one head in tossing a pair of coins is 1/2.

Reason: The sample space of two coin tossed is ={HH,TT,HT,TH}=4

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: a) both assertion and reason are correct and reason is correct explanation for assertion.7

7.) Assertion: The probability of getting a spade card from a well shuffled deck of 52 cards is 13.

Reason: The probability of getting less than 3 in a single throw of a die is 1/3.

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

8.) Assertion: -0.4 can not be the probability of an event.

Reason: The probability of an event can neither be a negative value, nor it can exceed unity.

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: a) both assertion and reason are correct and reason is correct explanation for assertion.

9.) Assertion: Three coins are tossed simultaneously. The probability of getting all heads is 1/8.

Reason: The chance of throwing 5 with an ordinary die is 1/6.

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

10) Assertion: The probability of getting a prime number when a die is thrown once is 2/3.
Reason: Prime numbers on a die are 2, 3, 5.

Answer: (d)

Direction: In the following questions, a statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as:
(a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
(b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of
Assertion (A).
(c) Assertion (A) is true but Reason (R) is false.
(d) Assertion (A) is false but Reason (R) is true

1.) Assertion: The runs scored by a batsman in 5 ODIs are 31,97,112, 63, and 12. The standard deviation is 25.79.

Reason: mean = total sum of number in data sets./ total number in data sets.

a) Both Assertion and Reason are correct and reason is correct explanation for the.

b) Both Assertion and Reason are false but reason is not correct explanation for assertion.

c) Assertion is correct but reason is false.

d) Both Assertion and reason are false.

Ans: a) both assertion and  reason are correct but  reason is  not correct explanation for assertion.

 2.) Assertion: the mode of the call received on 7 consecutive day 11,13,13,17,19,23,25 is 13.

Reason: Mode is the value that appears most frequent;

a)Both Assertion and Reason are correct and reason is correct explanation for the.

b)Both Assertion and Reason are false but reason is not correct explanation for assertion.

c)Assertion is correct but reason is false.

d)Both Assertion and reason are false.

Ans: a) both assertion and  reason are correct but  reason is  not correct explanation for assertion.

3.) Assertion: Frequency is the number of times a particular observation occurs in data.

Reason: Data can be grouped into class intervals such that all observations in that range belong to that class.

a) Both Assertion and Reason are correct and reason is correct explanation for the.

b) Both Assertion and Reason are false but reason is not correct explanation for assertion.

c) Assertion is correct but reason is false.

d) Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

4.) Assertion: Class width = upper class limit – lower class limit

Reason: Class mark =(Upper Class Limit+ Lower Class Limit)/2

a) Both Assertion and Reason are correct and reason is correct explanation for the.

b) Both Assertion and Reason are false but reason is not correct explanation for assertion.

c) Assertion is correct but reason is false.

d) Both Assertion and reason are false.

Ans: b) both assertion and reason are correct but reason is not correct explanation for assertion.

5) Assertion: If the value of mode and mean is 60 and 66 respectively, then the value of median is 64.

Reason: Median = (mode + 2 mean)/2

Answer: (c)

6) Assertion: The arithmetic mean of the following given frequency distribution table is 13.81.

Reason: x̅ = ∑ f_i x_i / ∑f_i 

Answer: (a)

7) Assertion: If the number of runs scored by 11 players of a cricket team of India are 5, 19, 42, 11, 50, 30, 21, 0, 52, 36, 27 then median is 30.

Reason: Median = (n+1)/2, if n is odd.

Answer: (d)