Question

A man went door to door posing as a goldsmith. He promised to bring back the glitter of old and dull gold ornaments. An unsuspecting lady gave a set of gold bangles to him which he dipped in a particular solution. The bangles sparkled like new but their weight was reduced drastically. The lady was upset, but after a futile argument, the man beat a hasty retreat. Can you play the detective to find out the nature of the solution he had used?

Answer 1

The solution he used was Aqua regia, a Latin word meaning ‘Royal Water’. It is a mixture of concentrated Hydrochloric acid and concentrated nitric acid in a ratio of 3 : 1. It is capable of dissolving metals like Gold and Platinum. Since the outer layer of the gold bangles was dissolved in aqua regia, their weight was reduced drastically.