Question

Will the chemical reaction take place when zinc is added to ferrous sulphate solution? Justify your answer.

Answer 1

Hint:We know that a chemical reaction is a process in which one or more substances also called as the reactants are converted into one or more different substances, known as the products. The reaction depends upon the basis of the reactivity of the reactants involved. We can determine the reactivity of the element from its position in the reactivity series.

Complete step-by-step answer:The reactivity series of metals also known as the activity series, refers to the arrangement of metals in the decreasing order of their reactivity.
So, the chemical reaction will take place when zinc is added to the ferrous sulphate solution as we know zinc is more reactive than iron so it will replace iron from the salt solution and will lead to the formation of zinc salt and iron will be produced. This type of reaction is called a single displacement reaction.
The reaction will proceed as:
$Zn + FeS{O_4} \to ZnS{O_4} + Fe$
Therefore, we see here that zinc has displaced the iron from the ferrous sulphate solution.
When zinc is added to the ferrous sulphate solution the color changes from green to colorless. Original green color was due to the presence of ferrous ions. The zinc sulphate solution formed is greyish black in color as iron metal is deposited.

Note: A displacement reaction is a chemical reaction in which one element is replaced by another element. The high-ranking metals in the activity series can only displace the low-ranking metals which means the low-ranking metal ions are readily reduced by the high-ranking metal ions. Also, in a single displacement reaction only color change takes place, no precipitate is formed.