Question

Normally, copper is less reactive metal and cannot liberate ${H_2}$ gas with acids. But, when a copper piece is dipped in concentrated ${H_2}S{O_4}$, the copper piece is found to disintegrate after a period of time. Give reason behind it.

Answer 1

Hint: The symbol Cu and atomic number 29 of copper is a chemical element. This is a flexible, malleable and ductile metal with very high electrical and thermal conductivity. A pure pinkish-orange colour is seen on the freshly exposed surface of pure copper.

Complete answer:
A chemical acid made up of the elements of sulphur, oxygen and hydride with molecular formula ${H_2}S{O_4}$ is sulphuric acid, commonly known as vitriol oil. It is colourless, odourless and viscous, water soluble and synthesized in strongly exothermic reactions. Sulphuric acid is an oxidising agent.
A Bronsted acid which is an effective oxidizing agent is an oxidizing acid. Every Bronsted acid is an oxidising agent, as the hydrogen gas can be reduced from the acidic proton. Many acids have properties other than the hydrogen ion that function as strong oxidants. In general, the anionic structure contains oxygen. That contains nitric acid, perchloric acid, chloric acid, chromic acid and sulfuric acid.
Only when concentrated, sulphuric acid shows its capacity for oxidizing, while other acids such as nitric acid or chromic acid may oxidize when diluted. In their basic solution, their conjugate bases can even oxidize. Therefore, only when heated is the oxidation potential of sulfuric acid significant.
If a part of copper is dipped into concentrate ${H_2}S{O_4}$, after a moment, it is observed to disintegrate, as ${H_2}S{O_4}$ is an oxidizing agent and by resulting reaction, it oxidizes copper.
$ \Rightarrow Cu + {H_2}S{O_4} \to CuS{O_4} + {H_2}$

Note: Copper is used as a heat and electrical conductor, as construction material and as a part in specific alloys in metal, including sterling silver used in jewellery for the preparation of marine equipment and coins and continuously used for temperature measurement in pressure gauges and thermocouples.