Industrial Chemistry — Set 1
Chemistry · औद्योगिक रसायन · Questions 1–10 of 40
Which process is used for the large-scale manufacture of Ammonia?
Correct Answer: D. Haber process
• **Haber process** = Synthesizes ammonia from nitrogen and hydrogen gases. • **450°C and high pressure** — Requires elevated temperature and pressure with iron catalyst. • 💡 Wrong-option analysis: A: Bessemer used for steel, not ammonia; B: Contact process for sulfuric acid; C: Solvay for sodium carbonate.
Which substance is used as a moderator in nuclear reactors?
Correct Answer: C. Graphite
• **Moderator** = Slows down fast-moving neutrons to maintain controlled chain reaction. • **Graphite structure** — Effective due to its layered crystal structure and neutron-absorbing properties. • 💡 Wrong-option analysis: A: Liquid sodium is coolant, not moderator; B: Cadmium is absorber, used for control rods; D: Boron compounds used in control rods.
In the manufacture of glass, which of the following is used as a flux to lower the melting point of silica?
Correct Answer: D. Sodium carbonate
• **Flux** = Substance that lowers melting point to make glass production more efficient. • **Sodium carbonate (soda ash)** — Reduces silica melting temperature from 1700°C to 1100°C. • 💡 Wrong-option analysis: A: Limestone is stabilizer added after flux; B: Lead oxide creates lead glass, not used as flux; C: Aluminium oxide is reinforcer.
Which catalyst is used in the Contact process for the manufacture of Sulfuric acid?
Correct Answer: C. Vanadium pentoxide
• **Vanadium pentoxide (V₂O₅)** = Catalyzes conversion of SO₂ to SO₃ efficiently at 450°C. • **Contact process** — Industrial method that oxidizes SO₂ with oxygen using this catalyst. • 💡 Wrong-option analysis: A: Iron oxide used in Haber process, not Contact; B: Platinum is expensive, rarely used industrially; D: Nickel too easily poisoned.
Which gas is primarily used in the industrial manufacture of vegetable ghee from oils?
Correct Answer: B. Hydrogen
• **Hydrogenation** = Adds hydrogen across double bonds in unsaturated oils to solidify them. • **Nickel catalyst** — Reaction occurs at 150-200°C with Ni catalyst under pressure. • 💡 Wrong-option analysis: A: Oxygen oxidizes oils, making them rancid; C: Nitrogen is inert, doesn't participate in the reaction; D: Helium too light and inert.
What is the primary ore used for the industrial extraction of Aluminium?
Correct Answer: D. Bauxite
• **Bauxite (Al₂O₃·2H₂O)** = Contains 45-60% alumina, making it economically viable for extraction. • **Hall-Héroult process** — Bauxite is first purified to alumina, then electrolyzed at 950°C. • 💡 Wrong-option analysis: A: Galena is lead sulfide ore; B: Haematite is iron ore; C: Magnetite also iron ore, not aluminum.
Which variety of coal is considered the highest grade due to its high carbon content?
Correct Answer: B. Anthracite
• **Anthracite** = Contains 85-98% carbon with highest heat value among all coal types. • **Clean burning** — Burns with blue flame, minimal smoke, and no clinker formation. • 💡 Wrong-option analysis: A: Bituminous contains 60-90% carbon, lower quality; C: Peat is lowest grade, earliest stage; D: Lignite contains only 25-35% carbon.
Which chemical is commonly used in the 'Vulcanization' of natural rubber?
Correct Answer: C. Sulfur
• **Vulcanization** = Process of adding sulfur and heating to create cross-links between polymer chains. • **1840s discovery** — Charles Goodyear discovered this process, revolutionizing rubber industry. • 💡 Wrong-option analysis: A: Carbon doesn't form sufficient cross-links; B: Silicon produces silicone, different material; D: Phosphorus creates brittleness.
The Solvay process is industrially used to manufacture which of the following?
Correct Answer: D. Sodium carbonate
• **Sodium carbonate (Na₂CO₃)** = Also called soda ash, essential chemical in glass and detergent industries. • **Solvay process** — Uses ammonia to absorb CO₂ from limestone in brine solution. • 💡 Wrong-option analysis: A: Sulfuric acid made by Contact process; B: Bleaching powder made from Cl₂ and Ca(OH)₂; C: Caustic soda from brine electrolysis.
Which element is added to iron to manufacture 'Stainless Steel'?
Correct Answer: B. Chromium
• **Chromium** = Forms protective oxide layer (Cr₂O₃) that prevents rust formation and corrosion. • **Minimum 10.5%** — Stainless steel must contain at least 10.5% chromium by mass. • 💡 Wrong-option analysis: A: Copper reduces tensile strength; C: Tin forms brittle alloy (bronze); D: Zinc reacts with stainless steel matrix.