1. Identify colour substances
2. Determine the structure of substances
3. Dry distillation of colouring substances
4. Separate the substances from a mixture
Option “D” is correct Chromatography is a separation technique used to separate the different components in a liquid mixture. The purpose of preparative chromatography is to separate the components of a mixture for more advanced use and thus a form of purification.
82. The poisonous gas accidentally released in Bhopal Gas Tragedy is –
Option “C” is correct Bhopal gas tragedy occured on the night of 2–3 December 1984 at the Union Carbide India Limited (UCIL) pesticide plant in Bhopal, Madhya Pradesh. Over 500,000 people were exposed to methyl isocyanate (MIC) gas and other chemicals leaked from UCIL.
83. Release of which among the following is the primary reason for depletion of the ozone layer?
Option “C” is correct The Chlorofluro carbon formed by chlorine, fluorine and carbon. They are often used as refrigerants, solvents, and for the manufacture of spongy plastics. It is the primary reason for depletion of the ozone layer.
84. Which of the following molecules is joined by a double covalent bond?
1.C L2
2.O2
3.N2
4.He
Option “B” is correct Oxygen atom is joined by double covalent bond.
85. The common name of sodium tetraborate decahydrate is _____.
1. Epsom salt
2. Gypsum
3. Borax
4. Galena
Option “C” is correct The common name of Sodium Tetraborate Decahydrate is Borax.
86. Who invented Antibiotics?
1. Joseph Lister
2. William Harvey
3. Robert Knock
4. Alexander Fleming
Option “D” is correct Antibiotics also called antibacterials, are a type of antimicrobial drug used in the treatment and prevention of bacterial infections. Alexander Fleming invented Antibiotic.
87. The Chemical formula of Methanol is _____.
1. C2HsOH
2.CH3(OH)2
3.CH3OH
4.CH4OH
Option “C” is correct Methanol is the simplest alcohol, being only a methyl group linked to a hydroxyl group. It is a light, volatile, colorless, flammable liquid with a distinctive odour very similar to that of ethanol (drinking alcohol). However, unlike ethanol, methanol is highly toxic and unfit for consumption. Chemical formula of Methanol is CH3OH.
88. The gas usually filled in the electric bulb with Argon is –
