Login

why is it so that copper reacts with H2SO4 and HNO3 only but not with HCl?

my school teacher says that copper reacts with sulphuric acid and nitric acid but not with hydrochloric acid and my tution sir says that copper doesnot reacts with acids at all.what is the real thing??

meritnation experts please!!!!!

A general equation for the reaction of a metal and acid is 

 metal + acid --------> metal salt + hydrogen gas

However, the above reaction is not true for all the metals. Only those metals will liberate hydrogen gas from the acid which are more reactive than hydrogen and hence are placed above hydrogen in the reactivity series. Copper is less reactive than hydrogen, therefore it is placed below hydrogen in the reactivity series. As a result, it will not liberate hydrogen gas from any acid. Now, both sulphuric acid and nitric acid are strong oxidising agents. Hence, they will oxidise copper metal to Cu2+ ion. However, no hydrogen gas will be formed, only copper metal will be oxidised here. On the other hand, HCl is not that strong oxidising agent, in fact its use as an oxidising agent is not too well known. Hence it does not react with copper metal at all.  

@ Alika, good effort. Keep it up!!!  

  • 0
View Full Answer

 Clean copper metal will not react with any acid, unless the acid is also an oxidising agent. This is because copper is below hydrogen in the activities series. (If you are very smart, you will notice that this is not really an explanation, just an impressive way of saying that copper is not reactive enough to react with acids.)

If the copper surface has been oxidised, the copper oxide will dissolve in acid.

If the acid is strongly oxidising, the copper can dissolve to make a solution of the copper salt. For example, copper dissolves in concentrated nitric acid to give you nitrogen oxides and copper nitrate in solution, and also in hot concentrated sulphuric acid to give you sulphur dioxide and copper hydrogensulphate in solution.

hope dis helps :)

(0).(0)

  • 0
What are you looking for?