Railway Science (Chemistry-Chemistry in Everyday life)

Total Questions: 63

1. Which of the following compounds is/are used in black and white photography ? [RRC Group D 17/08/2022 (Morning)]

Correct Answer: (c) Silver chloride and silver bromide both
Solution:

Silver Chloride has several disinfectant and antiseptic properties and is also used to treat mercury poisoning. Silver bromide is used in photography as a component of an emulsion that helps develop a photographic image.
Silver oxide (Ag₂O) is used as a mild oxidizing agent. For example, it oxidizes aldehydes to carboxylic acids.

2. A Chemical compound X is prepared by heating gypsum. It is white powder and used as a fire proofing material. Compound X is : [RRC Group D 17/08/2022 (Morning)]

Correct Answer: (a) Plaster of Paris
Solution:

Plaster of Paris (CaSO₄ . 1/2 H₂O). A white powder, used for the setting of fractured bones. Sodium Hydroxide (NaOH) - odorless white crystalline solid at room temperature, used in soaps and industries.
Washing Soda (Na₂CO₃ .10H₂O) - white crystalline solid, basic in nature, used in removing stains and laboratory reagents. Baking Soda (NaHCO₃) - is basic in nature, reduces acidity and is used in fire extinguishers, and cleaning of an oven.

3. Which of the following is not the use of bleaching powder ? [RRC Group D 17/08/2022 (Evening)]

(i) to make drinking water free from germs
(ii) in soda-acid fire extinguishers
(iii) as an oxidising agent in many chemical industries
(iv) for baking cakes

Correct Answer: (c) iv
Solution:

Uses of Bleaching Powder (Calcium Oxychloride, Ca(OCl)₂ : for bleaching dirty clothes and as a bleaching agent for cotton, a strong oxidizing agent, as a disinfectant, to decontaminate polluted water.

4. Caustic soda is generally NOT used in the ______. [RRC Group D 18/08/2022 (Afternoon)]

Correct Answer: (c) manufacture of ammonia
Solution:

Ammonia synthesis is the process by which ammonia is formed from nitrogen and hydrogen over a catalyst (usually iron). Uses of Caustic Soda (Sodium Hydroxide, NaOH): As a cleansing agent, manufacturing of washing soda, used as a drain pipe cleaner, unblocks drains, removes built-up grease from ovens, used to make soap and detergents, paper and pulp industry, fabric industry, etc.

5. To cook some foods faster we can use ________. [RRC Group D 22/08/2022 (Afternoon)]

Correct Answer: (c) baking powder
Solution:

Bleaching powder [Ca(ClO)₂] - bleaching agent for cotton and linen in the textile industry. Sodium Chloride (NaCl) - used in healthcare to help prevent patients from becoming dehydrated and food preservative.
Ammonium Chloride (NH₄Cl) - used as a nitrogen supply in fertilizers and electrolyte in dry cells.

6. Which flower of Himalaya has antiseptic properties and hence can help in the healing of bruises ? [RRC Group D 22/08/2022 (Afternoon)]

Correct Answer: (c) Brahma Kamal
Solution:

Antiseptic properties - used to treat fevers, bone ache, intestinal ailments, cough, and cold. Datura - analgesic, anthelmintic, anti-inflammatory, and used in the treatment of stomach and intestinal pain that results from worm infestation, toothache, and fever from inflammation.
Ricinus - exhibits anticonceptive, antidiabetic,antifertility,anti-inflammatory, antimicrobial,antioxidant,hepatoprotectiv e, insecticidal, and wound-healing activities.
Parthenium - used to treat skin inflammation, rheumatic pain, diarrhea, urinary tract infections, dysentery, malaria, and neuralgia.

7. Consider the statements given below and identify the correct answer [RRC Group D 22/08/2022 (Evening)]

Statement I: Washing soda is produced from sodium chloride.
Statement-II: It attacks dirt and grease to form water soluble products, which are then washed away on rinsing with water

Correct Answer: (d) Both the statements are true.
Solution:

Washing soda (Na₂CO₃ . 10H₂O)(synthesized through Solvay's process - involves the reaction of sodium chloride, ammonia and carbon dioxide in water) is produced from sodium chloride (NaCl).

8. A compound X is transparent crystalline solid. It has cleansing properties and is used in the manufacture of glass. Compound X is: [RRC Group D 23/08/2022 (Morning)]

Correct Answer: (d) washing soda
Solution:

Washing Soda (Sodium carbonate - Na₂CO₃ . 10H₂O) - Helps in removing permanent hardness from water. Baking soda (Sodium bicarbonate - NaHCO₃) - Used to relieve heartburn, sour stomach, or acid indigestion by neutralizing excess stomach acid.

9. The leaves of the _______ plant contain methanoic acid. [RRC Group D 23/08/2022 (Afternoon)]

Correct Answer: (c) nettle
Solution:

Nettle is an herbaceous plant that grows in the wild. Nettle leaves have stinging hair, which causes painful stings when touched accidentally due to the methanoic acid (CH₂O₂) secreted by them.
A traditional remedy is rubbing the area with the leaf of the dock plant which often grows beside the nettle. Tartaric acid (C₄H₆O₆) is the acid found in tamarind.
Acid present in lemons and oranges is Citric acid [HOC(CO₂H)(CH₂CO₂H)₂ ]. The acid present in tomatoes is Oxalic Acid (C₂H₂O₄).

10. Which gas is utilized during the preparation of bleaching powder ? [RRC Group D 24/08/2022 (Morning)]

Correct Answer: (c) Chlorine
Solution:

Bleaching powder {Calcium hypochlorite - Ca(OCl)₂} - Synthesized by the action of chlorine gas (produced from the chlor-alkali process) on dry slaked lime, Ca(OH)₂ .
Use - for bleaching dirty clothes in the laundry and as a bleaching agent for cotton and linen in the textile industry, As oxidizer (strong oxidizing agent) in many industries and as a disinfectant.