Bronze is an alloy of
- (a)Cu and Zn
- (b)Cu and Sn
- (c)Zn and Mg
- (d)Fe and Cu
Correct — B, Cu and Sn. Bronze is an alloy of copper with tin, copper being the major component. Adding tin to copper produces a metal that is harder than either parent, casts far better, and resists corrosion in air and in seawater. Those properties are why bronze was used for tools, weapons, statues, bells and ship fittings long before iron working spread — the Bronze Age is named after the alloy itself.
- (a)Cu and Zn — Copper with zinc is brass, not bronze. Brass is the yellower alloy of taps, screws, utensils and wind instruments; it is the single distractor most likely to cost the mark here.
- (c)Zn and Mg — Neither zinc nor magnesium is the base metal of bronze, and no common school-level alloy is formed from this pair. Bronze must contain copper as its major constituent.
- (d)Fe and Cu — Bronze contains no iron as a defining constituent. Iron alloyed with carbon gives steel, and with chromium and nickel gives stainless steel, but iron plays no part in the definition of bronze.
An alloy is a homogeneous mixture of a metal with one or more other metals or non-metals, made in order to obtain properties the pure metal lacks — greater hardness, better castability, resistance to corrosion, or a lower melting point. The two classic copper alloys are exactly the two this question forces apart: bronze is copper with tin, and brass is copper with zinc.
The whole item comes down to separating bronze from brass, and the two stay confusable because both are copper-based and both look golden-brown. The reliable memory hook is archaeological — the Bronze Age is defined by copper-tin metallurgy, so tin belongs to bronze and zinc then goes to brass by elimination. It is worth fixing the other school alloys in the same sweep, because UPSC and NDA both like to ask them as a matching list: solder is lead with tin, stainless steel is iron with chromium and nickel, and an amalgam is any alloy in which one component is mercury.
- Bronze is an alloy of copper and tin; brass is an alloy of copper and zinc.
- Alloying copper makes the metal harder, easier to cast and more resistant to corrosion than the pure metal.
- Solder is an alloy of lead and tin, valued because it melts at a low temperature.
- Stainless steel is iron alloyed chiefly with chromium and nickel.
- An amalgam is an alloy in which one of the constituent metals is mercury.
- Swapping bronze and brass, since both are copper alloys of similar colour.
- Assuming that any two metals named in an option must form a recognised alloy.
- Forgetting that copper, not tin, is the major component of bronze.
As direct recall of an alloy's composition, or as a match-the-list item pairing alloys with their constituent metals.
Which are the materials generally employed as solder in soldering operation in electronics?
- (a) Iron and tin
- (b) Lead and tin
- (c) Aluminum and lead
- (d) Aluminum and iron
Answer(b) Lead and tin
UPSC prelims asked the same alloy-composition skill on solder, where tin appears again — this time paired with lead rather than copper, which is exactly the discrimination these items reward.
Solder is an alloy of
- (a) Cu and Sn.
- (b) Fe and Zn.
- (c) Pb and Sn.
- (d) Ag and Zn.
Answer(c) Pb and Sn.
NDA-I 2021 ran the same question type on solder, and printed 'Cu and Sn' — the bronze answer — as one of its wrong options, so the two papers between them test the whole alloy table.
- practice — not a real PYQ
Brass is an alloy of
- (a)copper and tin
- (b)copper and zinc
- (c)lead and tin
- (d)iron and carbon
Answer(b) copper and zinc — copper with tin is bronze, lead with tin is solder, and iron with carbon is steel.
- practice — not a real PYQ
Which one of the following alloys contains mercury?
- (a)Bronze
- (b)Solder
- (c)Amalgam
- (d)Brass
Answer(c) Amalgam — by definition an amalgam is an alloy one of whose metals is mercury.