Q14. Identify the alloy among the following of which lead is a component.
[SSC MTS 2020-cycle Official Paper (26 October 2021, Shift 1)]
(A) Alnico
(B) Solder
(C) Nickel
(D) Constantan
Answer: (B) Solder
Explanation: Conventional soft solder is an alloy of tin and lead. Alnico is an alloy associated with aluminium, nickel and cobalt; constantan is mainly copper and nickel; and nickel is itself an element. Tin–lead solder has a comparatively low melting temperature.
Q13. An alloy is made by mixing metal A costing Rs. 1,000/kg and metal B costing Rs. 700/kg in the ratio 2 : 3. What is the cost of 15 kg of the alloy?
[CGPSC Civil Services 2020, CSAT Paper II]
(A) Rs. 9,800
(B) Rs. 8,200
(C) Rs. 12,300
(D) Rs. 12,800
Answer: (C) Rs. 12,300
Explanation: A 2 : 3 ratio in 15 kilograms gives 6 kilograms of metal A and 9 kilograms of metal B. The cost is (6 × 1,000) + (9 × 700), or Rs. 12,300. This is a weighted average based on constituent quantities.
Q12. Which metal is NOT a constituent of the alloy called German silver?
[SSC Junior Engineer (Civil) (25 September 2019, Morning)]
(A) Copper
(B) Zinc
(C) Silver
(D) Nickel
Answer: (C) Silver
Explanation: German silver, also called nickel silver, normally combines copper, zinc and nickel. Despite its name and silver-white appearance, it contains no elemental silver. The alloy can be used for cutlery, decorative fittings, instruments and other applications requiring an attractive finish.
Q11. Gunmetal is an alloy of:
[SSC MTS (2 August 2019, Shift 2)]
(A) Copper, zinc and lead
(B) Copper, lead and silver
(C) Copper, tin and zinc
(D) Copper, iron and nickel
Answer: (C) Copper, tin and zinc
Explanation: Gunmetal is a copper-based casting alloy mainly containing copper, tin and zinc. Some formulations also add lead. Its combination of strength, castability and resistance to corrosion makes it useful for valves, gears, bearings and pump or steam fittings.
Q10. Brass is a mixture of:
[WBCS Preliminary Examination 2019]
(A) Copper and zinc
(B) Copper and tin
(C) Copper, nickel and zinc
(D) Copper, aluminium and magnesium
Answer: (A) Copper and zinc
Explanation: Brass is principally copper mixed with zinc. Changing the zinc percentage changes its colour, strength and workability. Copper–tin alloy is commonly called bronze; a copper–zinc–nickel alloy is often called German silver. Brass is used for hardware, fittings and musical instruments.
Q9. Gold and copper are present in two alloys in the ratios 7 : 2 and 7 : 11. Equal quantities of both are mixed. What is the gold-to-copper ratio in the third alloy?
[RPSC RAS Preliminary Examination 2018]
(A) 7 : 5
(B) 7 : 12
(C) 14 : 13
(D) 2 : 11
Answer: (A) 7 : 5
Explanation: Choose 18 units of each alloy. The first contains 14 gold and 4 copper; the second contains 7 gold and 11 copper. The combined mixture has 21 units gold and 15 copper, which simplifies to 7 : 5.
Q8. Constantan is alloyed from which metals?
[RRC/RRB Group D (17 September 2018, Shift 2)]
(A) Nickel, titanium, iron and chromium
(B) Copper, nickel and manganese
(C) Nickel, chromium, manganese and iron
(D) Copper and nickel
Answer: (D) Copper and nickel
Explanation: Constantan is primarily an alloy of copper and nickel, often close to 55% copper and 45% nickel. Its electrical resistance varies comparatively little with temperature, making it useful in resistance wires, thermocouples and certain measurement instruments.
Q7. Which one of the following mixtures is homogeneous?
[SSC CHSL (21 March 2018, Shift 2)]
(A) Water and oil
(B) Starch and sugar crystals
(C) Graphite and charcoal
(D) Alloys
Answer: (D) Alloys
Explanation: Many common alloys are homogeneous mixtures because their components are distributed uniformly at the material scale. Brass and bronze are familiar examples. Oil and water separate into different phases, while the other options do not represent the same kind of uniform metallic mixture.
Q6. What are the main components of the alloy bronze?
[SSC CGL Tier I (16 August 2017, Shift 1)]
(A) Copper and zinc
(B) Copper and tin
(C) Zinc and nickel
(D) Aluminium and nickel
Answer: (B) Copper and tin
Explanation: Traditional bronze is an alloy of copper and tin. Tin increases hardness and makes copper more useful for castings, tools, statues and bearings. Copper with zinc forms brass instead. Different bronze grades may also include small quantities of other elements.
Q5. German silver is used to make ornaments and decorative articles. Why is this name given?
[UPSC CDS General Knowledge (14 February 2016)]
(A) It is a copper alloy containing silver
(B) Germans were the first to use silver
(C) Its appearance resembles silver
(D) It is an alloy of silver
Answer: (C) Its appearance resembles silver
Explanation: German silver, or nickel silver, is named for its silvery appearance rather than actual silver content. It typically contains copper, nickel and zinc. The resulting metal is fairly hard and corrosion-resistant and is useful for decorative items, utensils and instrument components.
