Which of the following is a chemical change?

The gas produced when zinc reacts with dilute hydrochloric acid is

The chemical reaction,$\mathrm{Cu}+2{\mathrm{AgNO}}_3 \to \mathrm{Cu}{\left({\mathrm{NO}}_3\right)}_2+2\mathrm{Ag}$ is an example of a

Diagram-based questions.

Ritu placed a few copper turnings in ferrous sulphate solution in a beaker as shown in the following figure.

Will she observe any changes after one hour? Give reason to your answer.

Rohan placed an iron nail in copper sulphate solution.

What will he observe after one hour?

What will be the colour change ?

Give a reason for the change in colour observed.

Write the chemical equation for the reaction.

Ananya placed a piece of copper in zinc sulphate solution. She did not observe any changes occurring. Can you explain, why ?

Can a plastic or wooden object be coated with a metal by electroplating ? Why ?