Here are 50 Assertion and Reason questions based on Chapter 16: Chemistry in Everyday Life of the CBSE Class 12 Chemistry syllabus, with explanations for each answer:
1. Assertion: Enzymes are biological catalysts.
Reason: Enzymes accelerate the rate of biochemical reactions
without being consumed in the process.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Enzymes are indeed biological catalysts that speed
up biochemical reactions without being consumed in the process.
2. Assertion: Aspirin is an analgesic.
Reason: Aspirin reduces fever by inhibiting the production of
prostaglandins.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Aspirin acts as an analgesic by inhibiting the
enzyme cyclooxygenase, which produces prostaglandins involved in pain and
inflammation.
3. Assertion: Antacids neutralize stomach acidity.
Reason: Antacids react with hydrochloric acid in the stomach to
form salts and water.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Antacids, such as sodium bicarbonate, neutralize
stomach acid (HCl) by forming salts and water, which reduces acidity.
4. Assertion: Soap and detergent are both surfactants.
Reason: Soap and detergent both help in the removal of dirt and
oil from surfaces by lowering the surface tension.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Both soap and detergent are surfactants that
reduce surface tension, allowing them to clean surfaces by emulsifying oils and
dirt.
5. Assertion: Washing soda is a good detergent.
Reason: Washing soda contains sodium carbonate, which
effectively removes dirt from clothes.
Answer: (B) Assertion is true, reason is true, but reason is
not the correct explanation for assertion.
Explanation: Washing soda (sodium carbonate) is not typically
used as a detergent. It is a cleaning agent that softens water and removes
grease, but it is not as effective as detergents in cleaning fabrics.
6. Assertion: Penicillin is an antibiotic.
Reason: Penicillin inhibits bacterial cell wall synthesis,
preventing bacteria from growing.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Penicillin works by inhibiting the enzyme
responsible for cell wall synthesis in bacteria, thereby preventing bacterial
growth.
7. Assertion: Caffeine is a central nervous system stimulant.
Reason: Caffeine increases the concentration of cyclic AMP,
which stimulates the release of adrenaline.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Caffeine acts as a stimulant by increasing cyclic
AMP concentration, which stimulates the release of adrenaline, resulting in
enhanced alertness.
8. Assertion: Sodium benzoate is used as a preservative in
food.
Reason: Sodium benzoate prevents the growth of bacteria and
fungi by lowering the pH of food.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sodium benzoate is an effective preservative as it
lowers the pH of the food, inhibiting the growth of microbes like bacteria and
fungi.
9. Assertion: Chloramphenicol is a broad-spectrum antibiotic.
Reason: Chloramphenicol inhibits bacterial protein synthesis by
binding to the ribosome.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Chloramphenicol inhibits bacterial protein
synthesis by binding to the bacterial ribosome, making it effective against a
wide range of bacteria.
10. Assertion: Soap molecules have both hydrophilic and
hydrophobic parts.
Reason: The hydrophilic part of soap interacts with water,
while the hydrophobic part interacts with grease.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Soap molecules are amphiphilic, meaning they have
both water-loving (hydrophilic) and water-hating (hydrophobic) parts. The
hydrophilic part interacts with water, and the hydrophobic part interacts with
grease or oil.
11. Assertion: Sulphur dioxide is used as a preservative in
dried fruits.
Reason: Sulphur dioxide prevents browning and inhibits
microbial growth in dried fruits.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sulphur dioxide acts as a preservative by
preventing the oxidation of phenolic compounds, which causes browning, and by
inhibiting microbial growth.
12. Assertion: Saccharin is a non-nutritive sweetener.
Reason: Saccharin provides a high sweetness without
contributing calories to the diet.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Saccharin is a non-caloric sweetener that provides
sweetness without contributing to the energy content of food.
13. Assertion: Ethanol is used as a solvent in medicines and
perfumes.
Reason: Ethanol is a good solvent because it is both polar and
non-polar in nature.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Ethanol has both polar (hydrophilic) and non-polar
(hydrophobic) properties, making it a versatile solvent in many applications,
including medicines and perfumes.
14. Assertion: Vitamin C is a water-soluble vitamin.
Reason: Vitamin C is an antioxidant that helps in the formation
of collagen in the body.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Vitamin C is water-soluble and acts as an
antioxidant, playing a key role in collagen formation, which is important for
skin, bones, and tissues.
15. Assertion: Amoxicillin is an antibiotic.
Reason: Amoxicillin prevents bacterial cell wall formation,
causing bacterial cell lysis.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Amoxicillin works by inhibiting bacterial cell
wall synthesis, leading to cell lysis and the elimination of bacteria.
16. Assertion: Aspirin is also used as an anticoagulant.
Reason: Aspirin inhibits the enzyme cyclooxygenase, which leads
to the reduction of thromboxane A2, preventing blood clot formation.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Aspirin inhibits cyclooxygenase (COX), leading to
a reduction in thromboxane A2 production, which prevents platelet aggregation
and clot formation.
17. Assertion: Vitamin A is essential for vision.
Reason: Vitamin A is a precursor to retinal, a component of the
light-sensitive molecule in the retina.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Vitamin A is converted into retinal in the body,
which is crucial for vision as it forms part of the molecule that detects light
in the retina.
18. Assertion: Synthetic dyes are more stable than natural
dyes.
Reason: Synthetic dyes are made using synthetic chemicals,
which offer better resistance to light and washing.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Synthetic dyes are more stable due to their
chemical structure, making them resistant to fading and washing compared to
natural dyes.
19. Assertion: Food preservatives extend the shelf life of food
products.
Reason: Preservatives inhibit the growth of microbes and
prevent food spoilage.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Preservatives inhibit microbial growth, preventing
spoilage and extending the shelf life of food products.
20. Assertion: Sodium bicarbonate is used in fire
extinguishers.
Reason: Sodium bicarbonate releases carbon dioxide when heated,
which helps in extinguishing fires.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sodium bicarbonate releases carbon dioxide gas
when heated, which suffocates the fire by cutting off the oxygen supply.
21. Assertion: Detergents are more effective than soaps in hard
water.
Reason: Detergents do not form insoluble salts with calcium and
magnesium ions in hard water.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Detergents are made with synthetic surfactants
that do not form insoluble salts with calcium and magnesium ions, making them
more effective in hard water than soaps.
22. Assertion: Proteins are essential for growth and repair of
tissues.
Reason: Proteins are composed of amino acids, which are
required for the synthesis of new cells and tissues.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Proteins are made of amino acids, which are
essential for the formation of new cells and tissues, aiding in growth and
repair.
23. Assertion: Chlorine is used in water purification.
Reason: Chlorine kills bacteria and other microorganisms by
oxidizing their cell structures.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Chlorine is a disinfectant that kills
microorganisms in water through oxidation, making it safe for drinking.
24. Assertion: Vitamin D is essential for the absorption of
calcium and phosphorus.
Reason: Vitamin D helps in the synthesis of proteins required
for the absorption of calcium and phosphorus in the intestine.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Vitamin D promotes the synthesis of transport
proteins in the intestines, which helps in the absorption of calcium and
phosphorus, critical for bone health.
25. Assertion: Acids like acetic acid are used in the food
industry.
Reason: Acetic acid is used as a preservative due to its
antimicrobial properties.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Acetic acid, found in vinegar, has antimicrobial
properties, making it useful as a preservative in the food industry.
26. Assertion: Paracetamol is commonly used as a pain reliever.
Reason: Paracetamol inhibits cyclooxygenase, which is involved
in pain and fever.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Paracetamol works by inhibiting cyclooxygenase
(COX), which reduces the production of prostaglandins involved in pain and
fever.
27. Assertion: Natural sugars are healthier than artificial
sweeteners.
Reason: Artificial sweeteners do not provide calories, whereas
natural sugars provide essential energy.
Answer: (B) Assertion is true, reason is true, but reason is
not the correct explanation for assertion.
Explanation: While natural sugars provide energy (calories), it
doesn't necessarily make them healthier than artificial sweeteners. Some
artificial sweeteners may have advantages in controlling blood sugar and calorie
intake.
28. Assertion: Epsom salt is used as a laxative.
Reason: Epsom salt contains magnesium sulfate, which increases
water in the intestines and facilitates bowel movement.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Epsom salt contains magnesium sulfate, which
attracts water into the intestines, helping to soften stools and relieve
constipation.
29. Assertion: Sodium hypochlorite is used in bleaching.
Reason: Sodium hypochlorite is a strong oxidizing agent that
breaks down the chromophores in dyes.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sodium hypochlorite works as a bleach by oxidizing
the chromophores in stains or dyes, breaking them down and removing the color.
30. Assertion: Fiber is an essential part of a balanced diet.
Reason: Fiber aids in digestion by helping to regulate bowel
movements and prevent constipation.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Fiber helps to improve bowel movements and
digestion by adding bulk to stool and preventing constipation.
31. Assertion: Starch is a polysaccharide.
Reason: Starch is made up of glucose units joined by glycosidic
bonds.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Starch is a polysaccharide consisting of long
chains of glucose molecules linked by glycosidic bonds.
32. Assertion: Chlorophyll is essential for photosynthesis.
Reason: Chlorophyll absorbs light energy and converts it into
chemical energy, which is essential for the process of photosynthesis.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Chlorophyll absorbs light, primarily in the blue
and red regions, and converts it into chemical energy used in photosynthesis.
33. Assertion: Caffeine is used to reduce fatigue.
Reason: Caffeine stimulates the central nervous system,
increasing alertness and reducing the perception of tiredness.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Caffeine stimulates the central nervous system by
increasing the concentration of cyclic AMP, enhancing alertness and reducing
tiredness.
34. Assertion: Sulfur is used in medicines.
Reason: Sulfur compounds have antibacterial and antifungal
properties.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sulfur compounds are known to possess
antibacterial and antifungal properties, which make them useful in treating skin
conditions and infections.
35. Assertion: Lactic acid is used in food preservation.
Reason: Lactic acid inhibits the growth of harmful bacteria by
lowering the pH of the food.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Lactic acid lowers the pH of food, preventing the
growth of harmful microorganisms, and is used as a preservative in fermented
foods.
36. Assertion: Soap is effective in hard water.
Reason: Soap forms insoluble salts in hard water, which makes
it less effective.
Answer: (C) Assertion is false, reason is true.
Explanation: Soap is not very effective in hard water because
it forms insoluble salts with calcium and magnesium ions, which reduces its
cleaning power.
37. Assertion: Tannins are used in leather tanning.
Reason: Tannins have the ability to cross-link collagen fibers
in animal hides, making them more durable.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Tannins, which are polyphenolic compounds, bind to
collagen fibers in animal hides, preventing decomposition and making the leather
more durable.
38. Assertion: The enzyme lipase breaks down fats into fatty
acids and glycerol.
Reason: Lipase is a protein that catalyzes the hydrolysis of
ester bonds in fats.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Lipase is an enzyme that catalyzes the breakdown
of fats (triglycerides) into fatty acids and glycerol through hydrolysis.
39. Assertion: Sweeteners like sucralose are used in diet
foods.
Reason: Sucralose is a non-caloric sweetener that is many times
sweeter than sugar.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sucralose is a non-nutritive sweetener, which
means it provides sweetness without adding calories to food.
40. Assertion: Aspirin is used to reduce pain and inflammation.
Reason: Aspirin inhibits cyclooxygenase, preventing the
production of prostaglandins, which mediate pain and inflammation.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Aspirin inhibits cyclooxygenase (COX), leading to
a reduction in prostaglandins, which are involved in pain and inflammation.
41. Assertion: Penicillin is effective against viral
infections.
Reason: Penicillin works by inhibiting bacterial cell wall
synthesis, making it effective against bacterial infections.
Answer: (C) Assertion is false, reason is true.
Explanation: Penicillin is effective against bacterial
infections, not viral infections, as it targets bacterial cell wall synthesis.
42. Assertion: Proteins are the building blocks of cells.
Reason: Proteins are composed of amino acids, which form the
structure and function of cells.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Proteins are made up of amino acids that serve as
the structural and functional components of cells, tissues, and organs.
43. Assertion: Vitamin E is an antioxidant.
Reason: Vitamin E protects cells from oxidative damage by
neutralizing free radicals.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Vitamin E is an antioxidant that protects cell
membranes from oxidative damage by neutralizing free radicals.
44. Assertion: Caffeine is used in medicines to treat asthma.
Reason: Caffeine is a bronchodilator that helps in the dilation
of the bronchial tubes, aiding in easier breathing.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Caffeine acts as a bronchodilator by relaxing the
muscles around the airways, making it easier to breathe, which is why it is
sometimes used in asthma treatment.
45. Assertion: Soap molecules have both hydrophilic and
hydrophobic ends.
Reason: The hydrophobic part of the soap molecule attracts oils
and grease, while the hydrophilic part interacts with water.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Soap molecules have a hydrophilic head
(water-attracting) and a hydrophobic tail (oil-attracting), which allows them to
emulsify oils and grease in water, enabling cleaning.
46. Assertion: Nitrogenous fertilizers increase the growth of
plants.
Reason: Nitrogen is an essential element for the synthesis of
proteins and chlorophyll in plants.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Nitrogen is a vital nutrient that aids in protein
and chlorophyll production, which are crucial for plant growth, leading to
enhanced growth when used as fertilizer.
47. Assertion: Sugars such as glucose are considered
carbohydrates.
Reason: Carbohydrates are composed of carbon, hydrogen, and
oxygen, and sugars like glucose fit this general formula.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Sugars like glucose are carbohydrates made up of
carbon, hydrogen, and oxygen atoms, following the general formula of
carbohydrates (C₆H₁₂O₆ for glucose).
48. Assertion: Antacids are used to treat acidity.
Reason: Antacids neutralize excess stomach acid by reacting
with hydrochloric acid (HCl) to form salt and water.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Antacids work by neutralizing excess stomach acid,
providing relief from acidity by forming salt and water in the neutralization
process.
49. Assertion: Alcohol is a useful solvent in the
pharmaceutical industry.
Reason: Alcohol dissolves both polar and non-polar compounds,
making it a versatile solvent.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Alcohol can dissolve a wide range of substances
due to its polar and non-polar nature, making it useful for dissolving various
compounds in pharmaceutical formulations.
50. Assertion: Vitamin C is essential for the synthesis of
collagen in the body.
Reason: Collagen is a protein that requires vitamin C for its
structural formation in connective tissues.
Answer: (A) Assertion is true, reason is true, and reason is
the correct explanation for assertion.
Explanation: Vitamin C is crucial for collagen synthesis as it
aids in the hydroxylation of proline and lysine residues in collagen, essential
for the stability and structure of connective tissues.