Multiple choice

Which of the following statements are false?

  1. 18-carot gold consists of Au 58%, Cu 12–28% and Ag 4–30%.
  2. Sterling-S alloy contains Ag 82.5% and Cu 17.5%.
  3. Naval brass is composed of Cu 60%, Zn 39.25% and Sn 0.75%.
  4. Dow’s metal consists of 93.8% Mg, 6% Al and 0.2% Mn.

  1. 1 and 2

  2. 2 and 3

  3. 3 and 4

  4. 1, 2 and 3

  5. 2, 3 and 4

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  1. 18-carot gold contains Au 75%, Ag 10–20% and Cu 5–15%. Gold 14-carot consists of Au 58%, Cu 12–28% and Ag 4–30%.
    1. Sterling-S (sterling silver) alloy is composed of Ag 92.5% and Cu 7.5%.
    2. The composition of Naval brass is Cu 60%, Zn 39.25% and Sn 0.75%.4. Dow’s metal is composed of 93.8% Mg, 6% Al and 0.2% Mn. Hence, both 1 and 2 are false.