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?

NCERT Class X
Science - Science

Chapter_Metals and Non Metals

Answer 1

The name of the solution is Aquarasia. It is made up of 1 part of conc. $HNO_{3}$ and 3 parts of conc. HCl. It is highly powerful and is also used to melt gold.

Answer 2

Aqua regia which is a mixture of 3 parts of concentrated HCl acid and 1 part of concentrated nitric acid dissolves gold. The man put the gold bangales in this solution. The outer dirty layer of gold bangales dissolved in aqua regia bringing out the shining bangales. The weight was reduced drastically.