51. Now-a-days yellow lamps are frequently used as street lights. Which of the following gases is used in these lamps?
1. Sodium
2. Neon
3. Hydrogen
4. Nitrogen
Option “A” is correct Now-a-days yellow lamps are frequently used as street lights. Sodium gas are used as street lamp.
52. Burning pyrites ore gives out –
1. Carbon dioxide gas
2. Sulphur dioxide gas
3. Nitrogen dioxide gas
4. Nitric oxide gas
Option “B” is correct The mineral pyrite, or iron pyrite, is an iron sulphide with the molecular formula Pyrite is used in commercial production of sulphur dioxide, for use in the paper industry and in the manufacture of sulphuric acid.
53. Which one of the following fuels causes minimum air pollution?
1. Kerosene oil
2. Hydrogen
3. Coal
4. Diesel
Option “B” is correct Hydrogen is the purest combustion fuel. Water is generated from burning of Hydrogen. While coal, kerosene oil and diesel are known as fossil fuel which generates, Carbon dioxide and many other harmful gases when it burns.
54. Which gas is used in the purification of drinking water?
Option “B” is correct Chlorine is presently an important chemical for water purification (such as in water treatment plants), disinfectants and in bleach.
55. Which of the following is a fossil fuel?
1. Alcohol
2. Ether
3. Water gas
4. Natural gas
Option “D” is correct Fossil fuels, including coal, oil and natural gas are currently the world’s primary energy sources.
56. Which one of the following pairs is not correctly matched?
1. Ascorbic acid – Lemon
2. Maltose – Malt
3. Acetic acid – Curd
4. Formic acid – Red Ant
Option “C” is correct Lactic acid is found in curd not Acetic acid. Formic acid occurs in the body of red ants and in the stings of bees.
57. What is the largest component of lower atmosphere, by total volume?
1. Oxygen
2. Nitrogen
3. Helium
4. Water Vapour
Option “B” is correct By volume, Nitrogen is the largest component of the lower atmosphere.
58. Acetic Acid is another name for which of the following?
Option “A” is correct Acetic acid is also known as vinegar.
59. The reaction of Copper Sulphate and Iron produces Iron Sulphate and __________.
1. Vinegar
2. Ash
3. Baking Soda
4. Copper
Option “D” is correct The reaction of Copper Sulphate and Iron produces Iron Sulphate and Copper. It is a single displacement reaction.
60. A __________ thread is actually stronger than a steel wire.
1. Wool
2. Cotton
3. Jute
4. Nylon
Option “D” is correct Nylon is an artificial fibre. It has high tensile strength, stiffness, excellent heat deflection temperature, and superior abrasion and wear resistance. Nylon thread is actually stronger than a steel wire.
Pyrite is used in commercial production of sulphur dioxide, for use in the paper industry and in the manufacture of sulphuric acid.