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ScienceClass 8ICSE

State the various uses of natural gas.

Answer Uses of natural gas: It is used to turn turbines for wind and solar energy This fossil fuel is used for the production of ammonia which itself is used for making It is a domestic fuel as Compressed Natural Gas or CNG, which is gas stored at high pressure, is also used in some households for heating and cooking purposes. Alternative for a transportation fuel used in low load vehicles requiring high fuel Liquefied Natural Gas or LNG is used to power vehicles such as off-road trucks and

ScienceClass 8ICSE

What is CNG? State its one use.

Answer Compressed Natural Gas (CNG) is a fuel source that is made from compressing natural gas to less than 1% of its standard atmospheric volume, or 3,600 PSI. CNG can be used in place of gasoline or diesel in any vehicle with a CNG conversion kit available or CNG engine.

ScienceClass 8ICSE

What are the advantages of using natural gas (or CNG) as a fuel?

Answer The advantages of using natural gas (or CNG ) as a fuel are: Natural Gas is a cleaner It can be easily stored and transferred through It is relatively more abundant than other fossil fuels e. coal and petroleum. It is also a safer fuel, as it is lighter than air and dissipates rather than It provides instant energy, which is why it is used in the oven cooking, as it does not require pre-

ScienceClass 8ICSE

What are the major products (or fractions) of petroleum refining? Give one use of each petroleum product.

Answer The major products (or fractions) of petroleum refining are: Petroleum gas Diesel Petrol Kerosene Lubricating oil Paraffin wax Bitumen Uses of petroleum refined products: Liquefied Petroleum Gas or LPG is used in households as well as in the Diesel and petrol are used as fuels for Diesel is generally preferred for heavy motor vehicles. Petrol is also used as a solvent for dry cleaning, whereas diesel is also used to run electric Kerosene is used as a fuel for stoves and jet Lubricating oil reduces wear and tear and corrosion of Paraffin wax is used to make candles, ointments, ink, crayons, Bitumen or asphalt is mainly used to surface

ScienceClass 8ICSE

What are the constituents of coal gas? State one use of coal gas.

Answer Coal gas is obtained as a byproduct while producing coke. Its smell is not very pleasant. It is a highly flammable gas as the main component of it is methane. Thus, if not regulated carefully, it can form a mixture with air resulting in explosions. Uses of coal gas: It is mainly used as a fuel in industries situated near coal processing It is more commonly used to provide heat for domestic and industrial

ScienceClass 8ICSE

State the uses of coke.

Answer Uses of coke: In the manufacture of In the extraction of metals (as a reducing agent).

ScienceClass 8ICSE

Describe how coal was formed. What is this process called?

Answer Dense forests got buried under the soil due to natural processes, millions of years ago. More and more soil got deposited over them and they got compressed more. This led them to get exposed to very high temperature and pressure. They slowly got converted into coal under these extreme conditions. The whole process of the formation of coal from dead vegetation is known as carbonization.

ScienceClass 8ICSE

What happens when coal is heated in the air? State the uses of coal.

Answer If coal is heated in the presence of air, then coal burns to produce mainly carbon dioxide gas, and no other useful products are obtained. It is a gaseous fuel that is obtained by the strong heating of coal in the absence of air during the processing of coal to get a coke.

ScienceClass 8ICSE

Explain why fossil fuels are exhaustible natural resources.

Answer The process of the formation of fossil fuels requires millions of years. Dead vegetation and animals that get buried deep inside the earth require high temperature and pressure for the formation of fossil fuels, which cannot be done in the laboratory. Thus, fossils are limited. Therefore, the use of fossil fuels at a rapid rate will lead to their exhaustion.

ScienceClass 8ICSE

State whether the following statements are true or false (a) Coke is almost pure from carbon. (b) Coal tar is a mixture of various substances. (c) Kerosene is not a fossil fuel. (d) CNG is more polluting than petrol. (e) Fossil fuels can be made in the laboratory.

Answer True True False (d)False (e) False

ScienceClass 8ICSE

Write the full form of PCRA.

Answer PCRA stands for Petroleum Conservation Research Association.

ScienceClass 8ICSE

Fill in the following blanks with suitable words (a) Fossil fuels are and (b) Coal contains mainly (c) The slow process of conversion of dead vegetation into coal is called (d) The process of separation of different constituents from petroleum is (e) The least polluting fuel for vehicle is (f) The burning of fossil fuel causes air and also causes global

Answer Fossil fuels are coal, petroleum, and natural gas. Coal contains mainly The slow process of conversion of dead vegetation into coal is called The process of separation of different constituents from petroleum is The least polluting fuel for vehicle is CNG The burning of fossil fuel causes air pollution and also causes global

ScienceClass 8ICSE