Question

The metal generally mixed with Gold while making ornaments is:
A) Zinc
B) Iron
C) Silver
D) Copper

Answer 1

Hint: Gold (Au) is a metal of Group (11) of the periodic table and is known as transition and malleable metal. It is a very soft metal and is alloyed with another metal to change its physical property and make it hardened to easily convert into ornaments.

Complete answer:
Pure gold is very soft in nature. Gold has to mix with any other metal to give it more strength, improve hardness, ductility and melting point. The process of combining two different metals to improve their physical and chemical properties is called as alloying and the compound formed is known as an alloy. Gold being a very soft metal on melting will easily melt away and it will not convert and mould into hard substance needs to be combined with copper or silver to change its property. Copper is used as a base metal to mix with gold and to make it stronger, harder and less brittle in nature. It acts as the best alloy to make ornaments. Since the Silver layer gets easily oxidized in nature and gets easily corroded, copper remains the best choice as a metal to mix with Gold. For three parts of Gold one part of copper is added to increase its malleability, luster and increased resistance power.

Hence the correct option is option (D), copper.

Note: Copper is preferred over silver due to its high electrical conductance and better resistance to corrosion it acts as a most suitable choice by the jewellers to mix with gold while making ornaments.