Why does hno3 react with copper

I put one of them on the table, opened the bottle marked nitric acid, poured some of the liquid on the copper and prepared to make an observation. But what was this wonderful thing which I beheld? The cent was already changed and it was no small change either.

A green-blue liquid foamed and fumed over the cent and over the table. The air in the neighborhood of the performance became colored dark red. A great colored cloud arose. This was disagreeable and suffocating. How should I stop this? I tried to get rid of the objectionable mess by picking it up and throwing it out of the window.

I learned another fact. Nitric acid not only acts upon copper, but it acts upon fingers. If the nitric acid is dilute, the copper will be oxidized to form copper nitrate with nitric oxide as a byproduct. If the solution is concentrated, the copper will be oxidized to form copper nitrate with nitrogen dioxide as a byproduct.

Both nitric oxide and nitrogen dioxide are noxious and potentially toxic at high levels; nitrogen dioxide is the ugly brown gas present in the smog haze over many cities. With the concentrated acid, the solution will first turn green, then greenish-brown, and finally blue once diluted with water.

Either reaction is highly exothermic and releases energy in the form of heat. Another way to understand this reaction is by breaking it down into two half-reactions, one for oxidation loss of electrons and the other for reduction gain of electrons. The speed of this reaction depends on the surface area of the copper; copper wire will react more quickly than copper bars, for example. In this tutorial, we discuss following topics.

Both reaction are redox reactions and have to consider about their oxidation numbers when reactions are being balanced. Copper is a reddish brown color metal and less reactive than other metals such as alkali metals and alkaline earth metals. HNO 3 is an oxoacid of nitrogen and a strong monobasic acid.

HNO 3 can behave as an oxidizing acid. Dilute nitric acid reacts with copper and produce copper nitrate Cu NO 3 2 , nitric oxide NO and water as products. In this reaction, copper is oxidized while nitric acid is reduced to nitric oxide.

Nitric oxide is a neutral gas. Concentrated nitric acid reacts with copper and produce copper nitrate Cu NO 3 2 , nitrogen dioxide NO 2 gas and water as products.

When Cu reacts with nitric acid, NO or NO 2 can be given as products according to the temperature and concentration of the acid solution. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why does copper react only with nitric acid? Asked 5 years, 10 months ago. Active 3 years, 6 months ago. Viewed 67k times.

Improve this question. Gaurang Tandon 8, 10 10 gold badges 55 55 silver badges bronze badges.