Man-Made Materials — Set 5
Chemistry · मानव निर्मित सामग्री · Questions 41–50 of 50
Which chemical compound is known as 'Plaster of Paris'?
Correct Answer: C. Calcium Sulfate Hemihydrate
• **Calcium Sulfate Hemihydrate** = The correct answer is 'Calcium Sulfate Hemihydrate'. • **mass** — When mixed with water, it rehydrates and sets into a hard solid mass of gypsum • 💡 Wrong-option analysis: A: Calcium Sulfate Dihydrate; B: Calcium Carbonate; D: Calcium Oxide
Which of the following is used as an 'Antiseptic' to clean wounds?
Correct Answer: C. Tincture of Iodine
• **Tincture of Iodine** = Tincture of iodine is a solution of 2-3% iodine in an alcohol-water mixture. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Benzene; B: Vinegar; D: Acetone
Which synthetic fiber is also known as 'Orlon' or 'Acrilan'?
Correct Answer: A. Acrylic
• **Acrylic** = Acrylic fibers are marketed under various brand names like Orlon due to their wool-like characteristics. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Nylon; C: Polyester; D: Rayon
What is the common name for the polymer 'Polytetrafluoroethylene'?
Correct Answer: C. Teflon
• **Teflon** = Teflon is a brand name for PTFE, famous for its non-stick properties. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Nylon; B: Bakelite; D: PVC
Which gas is used in 'Neon signs' to produce a bright orange-red glow?
Correct Answer: C. Neon
• **Neon** = Neon gas emits a brilliant red-orange color when an electric discharge is passed through it at low pressure. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Argon; B: Krypton; D: Helium
Which of the following is used in the manufacture of glass to lower the melting point of silica?
Correct Answer: C. Sodium Carbonate
• **Sodium Carbonate** = Sodium carbonate, or soda ash, acts as a flux in the glass-making process. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Alumina; B: Lead Oxide; D: Calcium Carbonate
What is 'Dry Ice' chemically?
Correct Answer: A. Solid Carbon dioxide
• **Solid Carbon dioxide** = Dry ice is carbon dioxide in its solid form, which exists at temperatures below -78. • (Contextual detail from explanation) • 💡 Wrong-option analysis: B: Frozen Nitrogen; C: Solid Methane; D: Solid Oxygen
Which material is used for making 'Pencil Lead'?
Correct Answer: B. Graphite and Clay
• **Graphite and Clay** = Graphite is a form of carbon that leaves a mark on paper because its layers slide off easily. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Charcoal; C: Lead; D: Coal
Which variety of coal is considered the highest quality due to its high carbon content?
Correct Answer: C. Anthracite
• **Anthracite** = Anthracite contains the highest percentage of carbon (over 86%) and the fewest impurities. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Lignite; B: Bituminous; D: Peat
Which chemical is used as an 'Indelible Ink' for marking fingers during elections?
Correct Answer: D. Silver Nitrate
• **Silver Nitrate** = Silver nitrate reacts with the salt on the skin to form silver chloride, which turns black when exposed to light. • (Contextual detail from explanation) • 💡 Wrong-option analysis: A: Potassium Permanganate; B: Magnesium Sulfate; C: Sodium Chloride