WBBSE Solutions For Class 8 School Science Chapter 4 Occurrence Of Carbon And Its Compounds In Nature Review Questions

Chapter 4 Occurrence Of Carbon And Its Compounds In Nature Review Questions MCQs

Question 1. Which of the following is used as an electrode?

  1. Coke
  2. Graphite
  3. Charcoal
  4. Pvc

Answer: 2. Graphite

Question 2. Dry ice is actually

  1. Solid carbon dioxide
  2. Ice mixed with CO2
  3. Ice below 0°c
  4. Glacial acetic acid

Answer: 1. Solid carbon dioxide

Read And Learn More WBBSE Solutions For Class 8 School Science Review Questions

Question 3. Which of the following is used as rocket fuel?

  1. Liquid hydrogen
  2. Unleaded petrol
  3. Diesel
  4. Kerosene

Answer: 1. Liquid hydrogen

Question 4. Which of the following has the highest calorific value?

  1. Coal
  2. Hydrogen
  3. Lpg
  4. Cng

Answer: 2. Hydrogen

Question 5. One organic greenhouse gas is

  1. CO2
  2. CH4
  3. N2O
  4. Water vapor

Answer: 2. CH4

Question 6. One inorganic greenhouse gas is

  1. CO2
  2. Ch4
  3. N2O
  4. C2H2

Answer: 2. CH4

Question 7. A crystalline allotrope of carbon is

  1. Soot
  2. Charcoal
  3. Gas carbon
  4. Diamond

Answer: 4. Diamond

Question 8. Which of the following is found in the shells of marine organisms?

  1. Na2CO3
  2. MgCO3
  3. CaCO3
  4. (NH4)2CO3

Answer: 3. CaCO3

Question 9. If one opens a bottle of soda water, the gas which evolves from it is

  1. CO2
  2. Ammonia
  3. Oxygen
  4. Hydrogen

Answer: 1. CO2

Question 10. The gas which is used as a fire extinguisher is

  1. CO2
  2. Ammonia
  3. Oxygen
  4. Water vapor

Answer: 1. CO2

Question 11. The anhydride of carbonic acid is

  1. C
  2. Co
  3. C6H6
  4. CO2

Answer: 4. CO2

Question 12. Which one of the following is not a greenhouse gas?

  1. Nitrogen
  2. Water vapor
  3. Methane
  4. CO2

Answer: 1. Nitrogen

Question 13. Carbon occurs as the native element in the earth’s crust in the form of

  1. Methane
  2. Gas carbon
  3. Diamond
  4. Carbon dioxide

Answer: 3. Diamond

Question 14. Identify the wrong statement.

  1. CO2 is lighter than air
  2. CO2 is not a supporter of combustion
  3. CO2 is soluble in water
  4. Solid CO2 is known as dry ice.

Answer: 1. CO2 is lighter than air

Question 15. Identify the wrong statement.

  1. Pvc is a biodegradable polymer
  2. Fullerene is a crystalline allotrope of carbon.
  3. Nylon was initially developed as a substitute for silk.
  4. A polymer is an aggregate of monomers

Answer: 1. Pvc is a biodegradable polymer

Question 16. CO2 is

  1. An acidic oxide
  2. A neutral oxide
  3. A basic oxide oxide
  4. An amphoteric

Answer: 1. An acidic oxide

Question 17. The existence of an element in different allotropic forms is due to the

  1. Different arrangements of the atoms
  2. Different methods of formation
  3. Different amounts of energy are associated with the formation of each allotrope
  4. All of these

Answer: 4. All of these

Question 18. The allotrope of carbon which has high adsorption capacity is

  1. Charcoal
  2. Graphite
  3. Coal
  4. Soot

Answer: 1. Charcoal

Question 19. The allotrope of carbon which is used for making gas masks is

  1. Charcoal
  2. Graphite
  3. Coal
  4. Lamp black

Answer: 1. Charcoal

Question 20. The allotrope of carbon which is used in arc lamps is

  1. Charcoal
  2. Graphite
  3. Gas carbon
  4. Acetylene

Answer: 3. Gas carbon

 

Chapter 4 Occurrence Of Carbon And Its Compounds In Nature Fill In The Blanks

Question 1. The phenomenon in which some elements exist in more than one form generally having the same chemical properties but some different physical properties in the same physical state is known as ____________.
Answer: Allotropy

Question 2. The different forms of an element having the same chemical properties but with different physical properties are called ____________.
Answer: Allotropes

Question 3. Carbon is stored in the shells of marine organisms as ____________.
Answer: Calcium Carbonate

Question 4. Carbon comprises nearly ____________ of the total mass of the body.
Answer: 50%

Question 5. Diamond is a very ____________ conductor of heat.
Answer: Good

Question 6. A suspension of graphite in oil is used as ____________
Answer: Lubricant

Question 7. Green plants absorb CO2 from the atmosphere and it is converted to ____________ by a process called photosynthesis.
Answer: Glucose

Question 8. Apart from carbon, two other elements which also have allotropes are ____________ and ____________
Answer: Sulfur phosphorous

Question 9. Chemically, graphite is ____________ reactive than diamond.
Answer: More

Question 10. CO2 constitutes approximately ____________ by volume in air.
Answer: 0.3%

Question 11. Diamond is ____________ conductor of electricity.
Answer: Poor

Question 12. The materials which are burnt to produce heat energy are known as ____________.
Answer: Fuels

Question 13. The CO2 gas is ____________ times heavier than air.
Answer: 1.5

Question 14. Fullerene is soluble in ____________
Answer: Beneze

Question 15. An aqueous solution of CO2 turns ____________ litmus. This proves that the aqueous solution of CO2 is ____________.
Answer: Blue, red, and acidic

Question 16. During fermentation of sugar by the action of enzymes, present in yeast, ____________ gas is obtained.
Answer: Co2

Question 17. When ____________ gas is passed through lime water, it turns milky due to formation of
Answer: CO2,CaCO3

Question 18. CO2 gas is absorbed by ____________solution.
Answer: caustic potash (KOH)

Question 19. ____________ radiation is primarily responsible for the sensation of heat.
Answer: IR (infra-red)

Question 20. Teflon is a high-molecular-weight compound consisting wholly of ____________ and____________ .
Answer: Carbon, Fluorine

Question 21. PVC is the abbreviation of ____________.
Answer: Polyvinyl Chloride

Question 22. ____________ properties of Teflon is utilized in cookware application.
Answer: Non-stick

Question 23. Chlorofluorocarbon is a ____________ gas.
Answer: Greenhouse

Question 24. The major component of cotton or straw is ____________
Answer: Cellulose

Question 25. ____________ is a biodegradable polymer.
Answer: Cellulose

 

Chapter 3 Occurrence Of Carbon And Its Compounds Identify As ‘True’ Or ‘False’

Question 1. Carbon is a metal.
Answer: False

Question 2. Diamond is a crystalline allotrope of carbon.
Answer: True

Question 3. Graphite is a good conductor of electricity.
Answer: True

Question 4. Graphite has a layered structure.
Answer: True

Question 5. Diamond is a very good conductor of heat. It has the highest thermal conductivity among the elements.
Answer: True

Question 6. Diamond is a good conductor of electricity.
Answer: False

Question 7. Pure diamond is colorless.
Answer: True

Question 8. CO2 is lighter than air.
Answer: True

Question 9. CO2 is not a supporter of combustion.
Answer: True

Question 10. When we burn fossil fuel, carbon from all these carbonaceous fuels are converted into CO2 and released into the atmosphere.
Answer: True

Question 11. Methanogenic bacteria which are available in wetlands and rain forests can decompose dead plants into methane (CH4).
Answer: True

Question 12. A suspension of coke in oil is used as a lubricant.
Answer: False

Question 13. Fullerene – a new allotrope of carbon was first characterized in 1985 in the laboratory by Smalley and Kroto.
Answer: True

Question 14. Charcoal has a remarkable property of adsorption.
Answer: True

Question 15. Among all the fuels, hydrogen has the least heating value.
Answer: False

Question 16. Coke can be used as fuel during metal extraction and as a reducing agent in redox reactions.
Answer: True

Question 17. Coal is primarily used as fuel.
Answer: True

Question 18. Lamp black is used as a pigment and used for making printing ink for use in the printing press.
Answer: True

Question 19. Gas carbon is used to make electrodes of batteries, arc lamps, or electrolytic cells.
Answer: True

Question 20. CO2 is insoluble in water and the solubility increases with temperature
Answer: False

Question 21. Soda water is made by dissolving soda in water under high pressure.
Answer: False

Question 22. An aqueous solution of CO2 turns blue litmus red.
Answer: True

Question 23. When a lighted magnesium filament is introduced in a gas jar filled with CO2, the metal filament burns very brightly
Answer: True

Question 24. Solid CO2 is called dry ice.
Answer: True

Question 25. The density of graphite is more than that of a diamond.
Answer: False

Question 26. A carbonate or bicarbonate of a metal in contact with a dilute mineral acid produces carbon dioxide gas.
Answer: True

Question 27. Methane is not a greenhouse gas.
Answer: True

Question 28. The average temperature of the earth is rising due to the enhanced greenhouse effect.
Answer: True

Question 29. PVC is highly fire-resistant.
Answer: True

Chapter 4 Occurrence Of Carbon And Its Compounds In Nature Match The Columns

 

1.

Column – A Column – B
A. Diamond 1. Amorphous allotrope of carbon
B. Charcoal 2. Crystalline allotrope of carbon
C. Graphite 3. Used in arc lamps
D. Gas carbon 4. Used as electrodes

Answer: A-2,B-1,C-3,D-4

2.

Column – A Column – B
A. Cellulose 1. Initially developed as a substitute for silk
B. PVC 2. Composite material of terylene and cotton
C. Nylon 3. Biodegradable polymer
D. Terrycot 4. Artificial polymer

Answer: A-3,B-4,C-1,D-2

3.

 Column -A Column – B
A. Methane 1. High adsorption property
B. Diamond 2. Used in non-stick cooking utensils
C. Charcoal 3. Greenhouse gas
D. Teflon 4. Used as the tip of the boring drill

Answer: A-3,B-4,C-1,D-2

Leave a Comment