On this Page we have given West Bengal Class 8 English Medium Science Solution Chapter 4 Occurrence of Carbon and its Compounds in Nature Question and Answer for our Students of West bengal Class 8 English Medium. Hope this following Question Answer will help our Students.
West Bengal Class 8 | Science | Occurrence of Carbon and its Compounds in Nature
Q.(1) MCQ
1.) What is the major component of living bodies?
A) Nitrogen
B) Oxygen
C) Carbon
D) Sulfur
Answer: Carbon
2.) Which of the following is a carbon compound?
A) Sodium chloride
B) Calcium carbonate
C) Hydrogen peroxide
D) Methane
Answer: Methane
3.) What are some small molecules that are carbon compounds?
A) Lipids and hormones
B) Calcium carbonate and proteins
C) DNA and RNA
D) ATP and lipids
Answer: ATP and lipids
4.) What are some materials that are made of carbonaceous compounds?
A) Furniture and instruments
B) Limestone and marble
C) Shells of marine animals
D) Nitrogenous bases in DNA
Answer: Furniture and instruments
5.) What is the role of trees in reducing the level of CO2 in the air?
A) They absorb CO2 through their roots
B) They emit oxygen, which reacts with CO2 to form water
C) They release CO2 during photosynthesis
D) They absorb CO2 during photosynthesis
Answer: They absorb CO2 during photosynthesis
6.) It is the process by which green plants, algae and cyanobacteria convert aerial CO2 into simple food?
A) Carbon fixation
b) Carbon assimilation
c) Carbon sequestration
d) Carbon mineralization
Answer: Carbon fixation
7.) Which of the following organisms can convert carbon monoxide (CO) to organic compounds?
A) Green plants
b) Algae
c) Cyanobacteria
d) Anaerobic bacteria
Answer: Anaerobic bacteria
8.) Identify the name given to the continuous cycling of carbon compounds through organic and inorganic world?
A) Carbon assimilation
b) Carbon sequestration
c) Carbon mineralization
d) Carbon cycle
Answer: Carbon cycle
9.) What happens when carbon dioxide reacts with rain water?
a) It forms carbonic acid
b) It forms bicarbonate ions
c) It forms calcium carbonate
d) All of the above
Answer: All of the above
10.) How is carbon dioxide released into the atmosphere through human activities?
A) Through photosynthesis by green plants
B) Through microbial degradation of organic material
C) Through combustion of fuels and cement manufacture
D) Through heating shells of marine organisms
Answer: Through combustion of fuels and cement manufacture
11.) What is the role of methane in global warming?
A) Methane reduces the amount of carbon dioxide in the atmosphere
B) Methane is a greenhouse gas and increases the average temperature of the earth
C) Methane is produced by green plants through photosynthesis
D) Methane Is released into the atmosphere through volcanic eruptions
Answer: Methane is a greenhouse gas and increases the average temperature of the earth
12.) How do oceans absorb carbon dioxide?
A) Through microbial degradation of organic material
B) Through the production of carbon dioxide by respiration of marine organisms
C) Through the release of carbon dioxide from marine algae
D) Through the absorption of carbon dioxide generated through human activities
Answer: Through the absorption of carbon dioxide generated through human activities
13.) What happens when shells of marine organisms are heated at a high temperature?
A) Carbon dioxide is released into the atmosphere
B) Carbon dioxide is absorbed from the atmosphere
C) Oxygen is released into the atmosphere
D) Oxygen is absorbed from the atmosphere
Answer: Carbon dioxide is released into the atmosphere
14.) These are symmetrically-shaped solid grains and are called
A) Atoms
B) Compounds
C) Crystals
D) Elements
Answer: Crystals
15.) Which of these elements can have more than one allotrope?
A) Carbon and sulfur
B) Carbon, phosphorus, and boron
C) Oxygen and sulfur
D) Oxygen, sulfur, and nitrogen
Answer: Carbon, phosphorus, and boron
16.) Define allotropy
A) The property of an element to exist in more than one physical form
B) The process of obtaining crystals from compounds
C) The physical property of symmetry in solid grains
D) The process of heating a substance to obtain a liquid
Answer: The property of an element to exist in more than one physical form
17.) How do allotropes of an element differ from each other?
a) In their chemical properties
b) In their molecular structures or crystal arrangements
c) In their solubility in water
d) In their boiling points
Answer: In their molecular structures or crystal arrangements
18.) Can allotropes of an element have different chemical properties?
a) Yes, in some cases
b) No, they always have the same chemical properties
c) Only if they have the same molecular structure
d) Only if they are made of different elements
Answer: Yes, in some cases
19.) What is the difference between crystalline and amorphous allotropes of carbon?
A) Crystalline allotropes are black and amorphous allotropes are white
b) Crystalline allotropes have a regular molecular structure, while amorphous allotropes consist of tiny crystals of graphite
c) Crystalline allotropes are soluble in water, while amorphous allotropes are not
d) Crystalline allotropes are denser than amorphous allotropes
Answer: Crystalline allotropes have a regular molecular structure, while amorphous allotropes consist of tiny crystals of graphite
20.) What is the difference in physical properties between crystalline allotropes of carbon?
A) They have the same physical properties
b) They differ considerably due to differences in their molecular structures
c) They differ considerably due to differences in their external appearance
d) They differ considerably due to differences in their chemical properties
Answer: They differ considerably due to differences in their molecular structures
21.) What is the direction of the applied force and slip of your finger when you rub it on powdered graphite?
A) The force and slip are in the same direction
b) The force is in one direction and the slip is in the opposite direction
c) The force is in a circular direction and the slip is in a straight direction
d) The force is in a straight direction and the slip is in a circular direction
Answer: The force is in one direction and the slip is in the opposite direction
22.) How are the carbon atoms arranged in graphite and diamond?
a) Graphite has a three-dimensional network, while diamond has parallel layers.)
b) Graphite has parallel layers, while diamond has a three-dimensional network.)
c) Both graphite and diamond have a three-dimensional network.)
d) Both graphite and diamond have parallel layers.)
Answer: Graphite has parallel layers, while diamond has a three-dimensional network.)
23.) Why does your finger slip when rubbed against graphite dust?
a) Because graphite is a good conductor of electricity
b) Because the attraction between the layers of graphite is weak
c) Because graphite is denser than diamond
d) Because graphite has large empty spaces
Answer: Because the attraction between the layers of graphite is weak
24.) Name the solid would be a better choice for a suspension in oil lubricant
A) Graphite
b) Diamond
c) Both would work equally well
d) Neither would work well as a lubricant
Answer: Graphite
25.) It would be a better choice for making the tip of a drill that bores through rock
A) Graphite
b) Diamond
c) Both would work equally well
d) Neither would work well as a drill tip
Answer: Diamond
26.) Which material has a greater thermal conductivity at room temperature, diamond or graphite?
A) Diamond
b) Graphite
c) Both have the same thermal conductivity
d) It depends on the temperature
Answer: Diamond
27.) Which material is a good conductor of electricity, graphite or diamond?
A) Graphite
b) Diamond
c) Both are good conductors of electricity
d) Neither is a good conductor of electricity
Answer: Graphite
28.) When burnt in sufficient oxygen, what do both graphite and carbon give?
A) Carbon monoxide
B) Carbon dioxide
C) Carbon trioxide
D) Carbon tetraoxide
Answer: Carbon dioxide
29.) Which of the following carbon allotropes is chemically less reactive than graphite?
A) Diamond
B) Fullerenes
C) Amorphous carbon
D) Charcoal
Answer: Diamond
30.) fullerenes are basically
A) Macromolecules
B) Polymers
C) Isotopes
D) Allotropes
Answer: Allotropes
31.) It is the potential application of fullerenes
A) Food production
B) Construction materials
C) Electronics and medicine
D) Clothing manufacturing
Answer: Electronics and medicine
32.)What is the property of charcoal that finds use in water purification?
A) Its high density
B) Its high melting point
C) Its adsorption property
D) Its conductivity
Answer: Its adsorption property
33.) It is the weak force of attraction between the molecule of pigment and the surface of charcoal called?
A) Adhesion
B) Absorption
C) Cohesion
D) Adsorption
Answer: Adsorption
34.) Name the property of charcoal which is used in the purification of gases
A) Its high density
B) Its high melting point
C) Its adsorption property
D) Its conductivity
Answer: Its adsorption property
35.) What is activated charcoal?
A) Charcoal produced from animal bones
B) Charcoal produced from coconut shells
C) Charcoal treated with oxygen to enhance its adsorption capacity
D) Charcoal used for making printing ink
Answer: Charcoal treated with oxygen to enhance its adsorption capacity
36.)Which allotrope of carbon is sometimes used to prepare printing ink?
A) Diamond
B) Graphite
C) Fullerene
D) Lamp black
Answer: Lamp black
37.) gas carbon used for
A) To make electrodes of batteries
B) To make printing ink
C) To prepare activated charcoal
D) To produce nanotechnology products
Answer: To make electrodes of batteries
38.) What is the basis of classification of carbon allotropes into crystalline and amorphous varieties?
A) Their external appearance
B) Their chemical properties
C) Their density
D) Their crystal size
Answer: Their external appearance
39.) Identify the source of wood charcoal
A) Plants
B) Animals
C) Fossil fuels
D) Minerals
Answers :Plants
40.)What is the potential application of graphene?
A) Water purification
B) Food production
C) Nanotechnology
D) Agriculture
Answer: Nanotechnology
41.) Which of the following is a common use of wood as a fuel
a) Generation of electricity
b) Running of factories
c) Cooking
d) Preparation of bricks
Answer: Cooking
42.) What is the main reason for the increasing demand of energy?
a) Decrease in population
b) Less urbanisation
c) Ever-increasing use of machines
d) Limited stock of fuels
Answer: ever-increasing use of machines
43.) It is the main aspect we need to focus on to conserve fuels
a) Using better quality coal in important sectors
b) Reducing the use of machines
c) Developing alternative sources of energy
d) Burning all the available fuels
Answer: Developing alternative sources of energy
44.) the refining of coal is called
A.) Combustion
B.) Fossilization
C.) Coal washing
D.) Coal conversion
Answer: Coal washing
45.) What is the percentage of carbon dioxide in air?
a) Less than 1%
b) More than 50%
c) Exactly 1%
d) 10%
Answer: Less than 1%
45.) What is the use of carbon dioxide in the production of urea?
a) It reacts with urea to produce ammonia
b) It reacts with ammonia to produce urea
c) It is used as a solvent in the production of urea
d) It has no role in the production of urea
Answer: It reacts with ammonia to produce urea
46.) How is soda used in the production of glass
a) It is used as a solvent
b) It is used as a raw material
c) It is used as a catalyst
d) It has no role in the production of glass
Answer: It is used as a raw material
47.) Dry ice is actually
a) A type of glass
b) A type of fertilizer
c) Solid carbon dioxide
d) A type of fire extinguisher
Answer: Solid carbon dioxide
48.)it is the result of the reaction between dilute hydrochloric acid and calcium carbonate?
A) Calcium chloride, carbon dioxide, and water are produced
b) Calcium carbonate, carbon dioxide, and water are produced
c) Calcium chloride, hydrogen gas, and water are produced
d) Calcium carbonate, hydrogen gas, and water are produced
Answer:)Calcium carbonate, carbon dioxide, and water are produced
49.) carbon dioxide accumulate in the jar during the preparation of carbon dioxide
A) Because carbon dioxide is lighter than air
b) Because carbon dioxide is heavier than air
c) Because carbon dioxide is denser than air
d) Because carbon dioxide is less dense than air
Answer:Because carbon dioxide is heavier than air
50.) the physical state of carbon dioxide at normal temperature and pressure
A) Liquid
b) Solid
c) Gas
d) Plasma
Answer: Gas
Q.(2) Short answer questions
(1) Name the carbon containing biological polymers ?
→ Proteins, carbohydrates, DNA, RNA
(2) How much amount of mass of human body is made up of carbon ?
→ 50% of mass of human body is made up of carbon.
(3) Give the chemical formula of limestone ?
→ CaCO3
(4) Give the chemical formula of calamine ?
→ ZnCO3
(5) Write one process of removal of carbon dioxide from the environment ?
→ Formation of shells of marine animals.
(6) Write one process of addition of carbon dioxide to the environment ?
→ By the process of respiration and oxidation of food.
(7) What do you mean by allotropes ?
→The compounds that differs in physical properties but having same chemical environment called as allotropes.
(8) Write the types of allotropes of carbon ?
→Crystalline allotropes
→Amorphous allotropes
(9) Write the examples of crystalline allotropes ?
→
- Diamond.
- Graphite
- Fullerene
(10) Explain about thermal conductivity of diamond and graphite ?
→Both diamond and graphite are good conductors of heat at room temperature.
(11) Explain about the electrical conductivity of diamond and graphite?
→
- Graphite is good conductor of electricity.
- Diamond is poor conductor of electricity.
(12) What about the chemical reactivity of diamond and graphite ?
→ Diamond is less reactive than graphite .
(13) Write to examples of amorphous allotropes of carbon.
→
- Coal
- Charcoal
- Gas carbon
(14) What do you mean by heating value or calorific value ?
→ The amount of heat generated on complex combustion of 1 kilogram of each fuel called as heating value or calorific value. ..
(15) Write the uses of coal ?
→
- Cooking
- Generation of electricity
- Preparation of bricks
(16) Write the use of petrol ?
→
- For making the chemicals
- For making the road oils etc.
- As fuel of vehicles.
(17) What are the uses of CNG ?
→ CNG can be used as a fuel for the vehicles
(18) What do you mean by coal washing?
→ Refining of coal is called as coal washing.
(19) What are the alternative sources of energy?
→ Resources of energy other than traditional fuels called as alternative sources of energy.
(20) Write the examples of alternative sources of energy ?
→
- Solar energy
- Wind energy
- Tidal energy
- Bio fuels.
(21) How the atomic energy used as a source of energy?
→ In an atom, neutrons and protons are bound to nucleus with an energy called as nuclear binding energy. If the nucleus in an atom is disintegrated then enormous amount of energy is generated. If this energy used properly then we can produce electricity.
(22) Name two atomic power stations in India ?
→
- Tarapur in Maharashtra
- Kalpakkam in Kerala
(23) Write hazardous effect on environment by combustion of fossil fuel?
→The combustion of fossil fuel in the environment leads to rise some carbon particles in the environment which causes several respiratory disorders like asthma.
(24) Write example of non-biodegradable polymer?
→
- Polyvinyl chloride (PVC)
- Refill of ball pens
- Discarded polybags
(25) Write example of biodegradable polymer ?
→
- Cellulose
- Peace of meat or fish
(26) What is biodegradation ?
→ Degradation of organic molecules by living organisms like some enzymes called as biodegradation.
(27) What is the use of Teflon ?
→Teflon is used to prepare nonstick utensils.
(28) What is the property of nylon ?
→Nylon is transparent , strong and what are resistant polymer.
(29) What is the use of PVC ?
→
- To prepare water pipes
- Used for insulation of wires
(30) Write the use of terylene ?
→Terylene is widely used to make clothes .
(31) Where do the greenhouse gases come from?
→ From the burning of fossil fuels and heating limestone in the cement factories.
(32) What is infrared radiation ?
→ In sunlight, there is presence of some invisible radiation which Primarily causes sensation of heat called as infrared radiation.
(33) What happens when carbon dioxide reacts with basic substances?
→ Carbon dioxide is acidic oxide which reacts with basic substances to produce carbonate compounds.
(34) How urea is prepared in the laboratory ?
→ Urea is prepared in the laboratory by reacting carbon dioxide with ammonia under suitable condition.
(35) Right uses of carbon dioxide in the chemical industry ?
→
- For the preparation of glass
- For the preparation of dry ice .
- For making fire extinguisher.
Also See: Previous Chapter Analysis of a Natural Phenomena Chapter Question Answer