Activity . Take a small amount of copper oxide in a beaker and add dilute hydrochloric acid slowly while stirring. Note the colour of the solution. What has happened to the copper oxide?
You will notice that the colour of the solution becomes blue-green and the copper oxide dissolves. The blue-green colour of the solution is due to the formation of copper(II) chloride in the reaction. The general reaction between a metal oxide and an acid can be written as – Metal oxide + Acid → Salt + Water Metal carbonate/Metal hydrogencarbonate + Acid → Salt + Carbon dioxide + Water