The aqueous solution of salt of a transition metal ion changes colour from pink to blue, when concentrated hydrochloric acid is added to it. The change in colour is due to:A. Evolution of hydrogen the changes the oxidation state of the metal ionB. Change ini the coordination number of the metal ion from 6 to 4 and formation of new species in solutionC. formation of a coordination complex of the metal ion with hydrochloric acidD. protonation of the metal ion.

The aqueous solution of salt of a transition metal ion changes colour

1.	The aqueous solution of salt of a transition metal ion changes colour from pink to blue, when concentrated hydrochloric acid is added to it. The change in colour is due to:A. Evolution of hydrogen the changes the oxidation state of the metal ionB. Change ini the coordination number of the metal ion from 6 to 4 and formation of new species in solutionC. formation of a coordination complex of the metal ion with hydrochloric acidD. protonation of the metal ion.
Answer» Correct Answer - C