TEXTBOOK EXERCISES
I. Choose the best
answer.
1.
The chemical mixed with LPG that helps in the detection of its leakage is
__________
a. methanol
b. ethanol
c. camphor
d. mercapton
[Answer: (d) mercapton]
2.
Which is known as syn gas?
a. Marsh gas
b. Water gas
c. Producer gas
d. Coal gas
[Answer: (b) Water gas]
3.
The unit of calorific value of fuel is__________
a) KJmol-1
b) KJg-1
c) KJkg-1
d) Jkg-1
[Answer: (c) KJ/kg]
4.
_____________ is the coal of superior quality.
a) Peat
b) Lignite
c) Bituminous
d) Anthracite
[Answer: (d) Anthracite]
5.
The main component of natural gas is__________
a) methane
b) ethane
c) propane
d) butane
[Answer: (a)
methane]
II. Fill in the
blanks.
1. Producer gas is a mixture of Carbon monoxide and nitrogen.
2. Methane is known as marsh gas.
3. The term petroleum means
4. Heating coal in the absence of
air is called
5. An example for fossil fuel is
III. Match the
following.
1. Octane rating - Diesel
2. Cetane rating - Methane
3. Simplest hydrocarbon - Petrol
4. Peat - Bown in colour
5. Lignite - First stage coal
[Answer:
(1 - c, 2 - a, 3 - b, 4 - e, 5 - d)]
1. Octane rating - c) Petrol
2. Cetane rating - a) Diesel
3. Simplest hydrocarbon - b) Methane
4. Peat - e) First stage coal
5. Lignite - d) Bown in colour
IV. Answer briefly.
1.
What do you mean by catenation?
Answer: (i) The property of carbon
atom to form bonds with itself resulting in a single large structure or chain
is called catenation.
2.
Mention the advantages of natural gas.
(i) It produces lot of heat as it is easily burnt.
(ii) It does not leave any residue.
(iii) It burns without smoke and so causes no pollution.
(iv) This can be easily supplied through pipes.
(v) It can be directly used as fuel in homes and industries.
3.
Expand CNG. List out its uses.
Answer: CNG - Compressed Natural Gas.
(i) It is the cheapest and cleanest fuel.
(ii) Vehicles using this gas produce less carbon dioxide and
hydrocarbon emission.
(iii) It is less expensive than petrol and diesel.
4.
Identify the gas known as syngas. Why is it called so?
Answer: Water Gas is also called as syngas or synthesis gas as it is used to
synthesize methanol and simple hydrocarbons. It is used as an industrial fuel
also.
5.
Anthracite is known as the highest grade coal. Give reason.
Answer:
(i) Anthracite is the highest grade coal.
(ii) It has a very light weight and the highest heat content.
(iii) Anthracite coal is very hard, deep black and shiny.
(iv) It contains 86-97% carbon and has a heating value slightly
higher than bituminous coal.
(v) It burns longer with more heat and less dust.
6.
Distinguish between octane number and cetane number.
Answer:
Octane
Number
• Octane rating is used for petrol
• It measures the amount of octane present in petrol.
• Octane number of petrol can be increased by adding benzene or
toluene.
• The fuel with high octane number has low cetane number
Cetane
Number
• Cetane rating is used for diesel
• It measures the ignition delay of the fuel in diesel engine.
• Cetane number of diesel can be increased by adding acetone.
• The fuel with high cetane number has low octane number
7. Name the places in Tamilnadu harnessing
wind energy from wind mills.
Answer: Wind mills are mostly located at Kayathar, Aralvaimozhi, Palladam and
Kudimangalam in Tamil Nadu.
8.
Solar energy is a non depleting energy. Justify.
Answer:
(i) Solar energy is the only viable fuel source of non -
depleting nature for, Sun provides a free and renewable source of energy.
(ii) It is the renewable type of energy without endangering the
environment.
(iii) It is the potential source to replace the fossil fuel in order
to meet the needs of the world. With the advancements in science and
technology, solar energy has become more affordable, and it can overcome energy
crisis.
V. Answer in detail.
1.
Explain the different types of coal.
(a)
Lignite:
(i) Lignite is a brown coloured coal of lowest grade.
(ii) It has least content of carbon. The carbon content of
lignite is 25 - 35%.
(iii) Lignite contains a high amount of water and makes up
almost half of our total coal reserves.
(iv) It is used for electricity generation.
(v) It is used to generate synthetic natural gas and produce
fertilizer products.
(b) Sub-biturninous:
(i) When lignite becomes darker and harder over time,
sub-bituminous coal is formed.
(ii) Sub-bituminous coal is a black and dull coal.
(iii) It has higher heating value than lignite and contains
35-44% carbon.
(iv) It is used primarily as fuel for electricity power
generation.
(v) This coal has lower sulfur content than other types and burns
cleaner.
(c) Bituminous:
(i) With more chemical and physical changes, sub-bituminous coal
is developed into bituminous coal.
(«) It is dark and hard. It contains 45-86% carbon. It has high
heating value.
(Hi) It is used to generate electricity.
(iv) Other important use of this coal is to provide coke to iron
and steel industries.
(v) By-products of this coal can be converted into different
chemicals which are used to make paint, nylon and many other items.
(d) Anthracite:
(i) It is the highest grade coal. It is hard and dark black in
colour.
(ii) It has a very light weight and the highest heat content.
(iii) Anthracite coal is very hard, deep black and shiny.
(iv) It contains 86-97% carbon and has a heating value slightly
higher than bituminous coal.
(v) It burns longer with more heat and less dust.
2.
What is known as destructive distillation? Write about the products obtained
from fractional distillation of petroleum.
Answer: Products obtained from fractional distillation of petroleum
have a number of uses :
(i) Liquefied Petroleum Gas or LPG is used in houses as well as
in the industry.
(ii) Diesel and petrol are used as fuels for vehicles. It is
also used to run electric generators.
(iii) Petrol is used as a solvent for dry cleaning.
(iv) Kerosene is used as a fuel for stoves and also in jet
planes.
(v) Lubricating oil reduces wear and tear and corrosion of
machines.
(vi) Paraffin wax is used to make candles, ointments, ink,
crayons, etc.
(vii) Bitumen or asphalt is mainly used to surface roads.
3.
Explain the different types of fuel gases.
Answer: Fuels are classified into solid, liquid and gaseous fuels
according to their physical state.
(a) Solid
fuels:
(i) Fuels like wood and coal are in solid state and they are
called solid fuels.
(ii) This type of fuel was the first one to be used by man.
(iii) These fuels are easy to store and transport.
(iv) The production cost is also very low.
(b) Liquid
fuels :
(i). Most of the liquid fuels are derived from the fossil
remains of dead plants and animals petroleum oil, coal tar and alcohol are some
of the liquid fuels.
(ii) These fuels give more energy on burning and burn without
ash.
(c) Gaseous
fuel:
(i) Coal gas, oil gas, producer gas and hydrogen are some of the
gaseous fuels.
(ii) It can be easily transported through pipes and they do not
produce pollution.
Related Topics
Privacy Policy, Terms and Conditions, DMCA Policy and Compliant
Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.