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?
ScienceClass 10CBSEAnswered 27 Mar 2026
Answer
Solution: The goldsmith used a solution called Aqua regia which is referred to as royal water in Latin. It is the mixture of concentrated hydrochloric acid and concentrated nitric acid in the ratio of 3:1. Aqua regia is capable of dissolving noble metals like gold and platinum. When upper-layer of dull gold ornament is dissolved they lose their weight.
Suggested Q&A
Science · Class 10- ScienceClass 10Explain why generally metals are solid at room temperature, but mercury is a liquid.
- ScienceClass 10What is the role of a flux in the metallurgical process?
- ScienceClass 10Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas?
- ScienceClass 10Why should curd and sour substances not be kept in brass and copper vessels?
- ScienceClass 10You are given three test tubes. The three test tubes contain distilled water, an acidic solution and the basic solution, respectively. There is only red litmus paper available in order to identify what is there in each test tube. How will you find out what is in each of the test tubes?
- ScienceClass 10Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron).
- ScienceClass 10Differentiate between metal and non-metal on the basis of their chemical properties.
- ScienceClass 10You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
- ScienceClass 10Give reasons (a) Platinum, gold and silver are used to make jewellery. (b) Sodium, potassium and lithium are stored under oil. (c) Aluminium is a highly reactive metal, yet it is used to make utensils for cooking. (d) Carbonate and sulphide ores are usually converted into oxides during the process of extraction
- ScienceClass 10What type of oxides are formed when non-metals combine with oxygen?