Chemistry In Everyday Life Book Back Questions 8th Science Lesson 15
8th Science Lesson 15
15] Chemistry In Everyday Life
Book Back Questions with Answer and Do You Know Box Content
Do you know?
Propane is used in LPG cylinders. Since it is an odouress gas, any leakage cannot be detected. Hence, a chemical by name Mercaptan is mixed with LPG to help in detection of any leakage of LPG.
The average composition of CNG
| Constituents | Percentage |
| Methane | 88.5 |
| Ethane | 5.5 |
| Propane | 3.7 |
| Butane | 1.8 |
| Pentane | 0.5 |
Moderate temperature and humidity is needed to keep paintings and other ancient artifacts from being destroyed by environmental factors. Thus natural gas is used in museums to protect the monuments.
Producer gas is known by different names in different countries. It is referred as wood gas in USA and as Suction gas in UK.
People in ancient cultures used crude oil for binding materials. It was also used as a sealant for water proofing various surfaces.
It is also known as black diamond owing to its precious nature. On destructive distillation, 1000 kg of coal gives 700 kg of coke, 100 litres of ammonia, 50 litres of coal tar and 400 m3 of coal gas.
The first oil well in the world was drilled in Pennsylvania, USA in 1859. The second oil well was drilled in Makum, Assam, India in 1867.
Hydrogen – The future fuel. Hydrogen could be the best alternative fuel in the future. It is a clean fuel as it gives out only water while burning. Moreover, it has the highest energy content. It does not pollute air.
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
2. Which is known as syn gas?
(a) Marsh gas
(b) Water gas
(c) Producer gas
(d) Coal gas
3. The unit of calorific value of fuel is _________
(a) KJmol-1
(b) KJg-1
(c) KJkg-1
(d) Jkg-1
4. ____________ is the coal of superior quality.
(a) Peat
(b) Lignite
(c) Bituminous
(d) Anthracite
5. The main component of natural gas is _____________
(a) Methane
(b) Ethane
(c) Propane
(d) Butane
Fill in the blanks:
1. Producer gas is a mixture of ____________ and ________.
2. _____________ 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 _______________.
Match the following:
1. Octane rating – diesel
2. Cetane rating – methane
3. Simplest hydrocarbon – petrol
4. Peat – brown in colour
5. Lignite – first stage coal
Answers:
Choose the best answer:
1. mercapton 2. Water gas 3. KJkg-1 4. Anthracite 5. methane
Fill in the blanks:
1. Carbon Monoxide and Nitrogen 2. Methane 3. Rock oil 4. Destructive distillation 5. Coal
Match the following:
1.Octane rating – Petrol
2.Cetane rating – Diesel
3.Simplest hydrocarbon – Methane
4.Peat – First stage coal
5.Lignite – Bown in Colour