Question

The change of colour from blue to green is because displaces from its salt solution.

• A. iron
• B. copper
• C. platinum
• D. lead
• E. gold
• F. silver

Answer 1

Answer: (A), (B)

copper

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> The blue colour of the solution is due to the ${\mathrm{Cu}}^{2+}$ ions. Iron being more reactive than copper displaces it from its salt solution. ${\mathrm{Fe}}^{2+}$ ions are pale green coloured. So the colour of solution changes from blue to green.