One day Reeta went to a jeweller’s shop with her mother. Her mother gave old gold jewellery to the goldsmith to polish. Next day when they brought the jewellery back, they found that there was a slight loss in its weight. Can you suggest a reason for the loss in weight?

 

Answer

To polish an ornament, the goldsmith dips the gold ornament in aqua regia. Aqua regia is a mixture of nitric acid and hydrochloric acid. After getting dipped in the aqua regia, the outer layer of the gold dissolves in the solution and the shiny part appears. Due to the dissolving of some part of the ornament, it’s weight reduces.

  1. Class 8
  2. Chapter 4 Class 8 - Materials : Metals And Non-Metals

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.