3

MAX TIME: 45 mins

MAX MARKS: 20

1.  Fill in the blanks

(1 x  5 = 5 marks)

      a. Cu₂S acts as ______ agent in Bassemerisation process.

      b. CaSiO₃ is known as _______ in extraction of iron.

      c. SO₂ is the product of ________ of sulphide ores.

      d. ZnO can be reduced by ________.

      e. ________ forms greenish layer due to basic copper carbonate.

2.  Why can Zn replace hydrogen from dil. HCl?

(2 marks)

3.  a. Show on a diagram the transfer of electrons between the atoms in the formation

of MgO. Write symbols of cation and anion present in MgO.

(2 marks)

4.  Why do non-metals not conduct

electricity? Also, name one non-metal that conducts electricity.

(3 marks)

5.  Write balanced chemical equations for the following:�

(3 marks)

      a. Dilute sulphuric acid reacts with aluminium powder.

      b. Dilute hydrochloric acid reacts with sodium carbonate.

      c. Carbon dioxide is passed through lime water.

6.  Give the steps involved in the extraction of metals of low and medium reactivity from

their respective sulphide ores.

(5 marks)