Which metal is well cast and has good machinability, is corrosion resistant, conducts heat well, and is an alloy of copper and zinc; used for musical instruments, screws, and water fittings?

• A. Brass
• B. Bronze
• C. Copper
• D. Tin

Answer: (A)

Brass is the copper–zinc alloy that fits all the clues. Adding zinc to copper makes the material easier to cast and machine, while still offering good corrosion resistance and solid heat conduction. This combination, along with the right zinc content, gives brass its characteristic bright color and workability, which is why it’s used for screws and water fittings. In musical instruments, brass’s color and the way it vibrates contribute to its distinctive tone and projection. The other materials don’t match because bronze is a copper–tin alloy and behaves differently in terms of machinability and corrosion; copper by itself is not an alloy of copper and zinc; tin is simply an element, not an alloy with copper.