question_answer

  Aqueous solutions of zinc sulphate and iron sulphate were taken in test tubes I and II by four students A, B, C and D. Metal pieces of iron and zinc were dropped in the two solutions and observations made after several hours were recorded in the form of table as given below.

Student	Metal	Solution	Colour change of solution	Deposit/coating  obtained
A	Fe		Turned green	Silvery grey deposit
	Zn		No change	No change
B	Fe		No change	Black deposit
	Zn		Colour faded	Grey coating
C	Fe		No change	No change
	Zn		Turned colourless	Black deposit
D	Fe		No change	Grey deposit
	Zn		No change	Black deposit

Which student has given the correct report?

Answer:

                  Student C (a) Fe is less reactive than zinc. So No reaction (b) Zn is more reactive than Fe, so it displaces iron as follows