What are alloys? How are they made? Name the constituents and uses of brass, bronze and solder.

Four metal A, B, C and D are added to the following aqueous solutions one by one. The observations made are tabulated below:

Answer the following questions based on the above observations:

(a) Which is the most active metal and why?

(b) What would be observed if B is added to a solution of copper (II) sulphate and why?

(c) Arrange the metal A, B, C and D in order of increasing reactivity.

(d) The container of which metal can be used to store both zinc sulphate solution and silver nitrate solution?

(e) Which of the above solutions can be easily stored in a container made up of any of these metals?

Sample of five metals ‘A’, ‘B’, ‘C’, ‘D’ and ‘E’ was taken and added to the following solution one by one. The results obtained have been tabulated as follows.

Use the above table to answer the following questions about the given metals.

(a) Which of them is most reactive and why?

(b) What would you observe if ‘B’ is added to CuSO₄?

(c) Arrange ‘A’, ‘B’, ‘C’, ‘D’ and ‘E’ in the increasing order of reactivity.

(d) Container of which metal can store zinc sulphate and silver nitrate solution?

(e) Which of the above solution(s) can be stored in a container made of any of these metals and why?

(a) What is meant by corrosion? Name any two methods used for the prevention of corrosion.

(b) Suppose you have to extract metal M from its enriched sulphide ore. If M is in the middle of the reactivity series, write various steps used in extracting this metal.

Reema’s maid fainted in her house. Reema took her maid to doctor. After check-up Doctor fond she suffered from anaemia Doctor advised her to take vegetables and fruits rich in iron. Doctor gave her some folic acid tablets which contain iron (II) sulphate. Reema helped her maid financially also.

(a) What values are possessed by Reema?

(b) Deficiency of which metal cause anaemia?

(c) What is a formula of folic acid?