Metals and non-metals-Important question with answer

 CHAPTER-3 METALS AND NON METALS

MULTIPLE CHOICE QUESTIONS

1.    1.  Which of the following is not a property of metals?

        (a)  Conduction

     (b)  Sonorous    

      (c)  Dullness

      (d)  Ductility

  2.      Metals are refined by using different methods .Which of the following metal is refined by electrolytic refining?

                 (i) Au (ii) Cu (iii) Na (iv) K

        (a)  (i) and (ii)

        (b)  (i) and (iii)G

        (c)  (ii) and (iii)

        (d)  (iii) and (iv)

    3.       Which of the following contains mercury as one of its constituents?

           (a)  Stainless Steel

       (b)  Alnico

        (c) Solder

        (d) Zinc amalgam

    FILL IN THE BLANKS

    4.        Aqua  regia consists of         parts of conc. HCl and       parts of conc HNO3.

    5.                                     is a liquid non-metal.

    6.                          is an amphoteric oxide.

     ONE MARK QUESTIONS

    7.      Name one metal which is a good conductor of electricity and one which is a poor conductor of electricity.

        8.      Why are food cans coated with tin and not with zinc?

        9.      Give the role of anhydrous calcium chloride in the process of roasting.

        ASSERTIONS AND REASONS

        For the question numbers 10, 11 and 12, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

      (a) Both A and R are true and R is the correct explanation of A.

   ( b) Both A and R are true but R is not the correct explanation of A

       c) A is true but R is false.(

      d) A is false but R is true

     10 . assertion: Iron is found in the free state in nature. 

            Reason: Iron is a highly reactive element.

       11.    Assertion: The thermite welding process is based on reducing the property of iron.

         Reason:    The reduction of metal oxide to form metal by using aluminium powder is called thermite reaction.

      12.    Assertion: Magnesium chloride is covalent.

      Reason:    Metals and non-metals react by mutual transfer of electrons.

     THREE MARK QUESTIONS1

3.  (a) A zinc rod was dipped in the CuSO4 solution. After a certain time, copper from the solution was deposited on the zinc rod. State the reason why did it happen. Give the chemical equation of the reaction involved.(b)Why should the metal sulphides and carbonates be converted to metal oxides in the process of extraction of metal from them?An ore on heating in air produces sulphur dioxide.

         (a) Which process would you suggest for its concentration?

         (b)  Describe briefly any two steps involved in the conversion of concentrated ore into related metal.

      15.    Give a reason for the following:

        (a) Ionic compounds have a high melting point and boiling point.

        (b) Ionic compounds conduct electricity in a molten state.

        (c) Ionic compounds are solids at room temperature and are somewhat hard.

     16.    What happens when

        (i)  ZnCO3 is heated in the absence of oxygen?

        (ii)  A mixture of Cu2O and Cu2S is heated?

        (iii)   A copper coin is kept immersed in a solution of silver nitrate for some time.

        FIVE MARK QUESTIONS

        17.    (a) In the formation of compounds  between two atoms A and B, A loses two electrons and  B gains one electron.

             (i)  What is the nature of the bond formed between A and B?

            (ii)  Suggest the formula of the compound formed between A and B.

            (b) Explain the formation of the MgCl2 molecule.

            (c) Write the electron dot structure of oxygen.

        18.    (a)What is meant by the refining of metals?

        (b)Generally, no hydrogen gas is evolved when metals react with dilute nitric acid. Why? (c)Write the chemical name of the coating that is formed  on silver and copper articles. (d)How do the properties of iron change when:

            (i)  A small quantity of carbon is mixed with it? 

         (ii)Nickel and chromium  are  mixed with it?

       19.    (a)You are provided with three metals Sodium, Magnesium, and copper. Using only water as the reactant how will you identify them?

         (b)Hydrogen is not a metal but it has been assigned a place in the reactivity series of metals. Explain.

        20.    CASE STUDY

            Answer question numbers 20 (a) to 20 (d) based on your understanding of the following paragraph and the related studied concepts.

        A customer approached a newly  trained Goldsmith and asked him to make ornaments. For   this, he gave advance money. The Goldsmith bought a bar of 24-carat gold and tried to make ornaments from it. He was not as successful as the gold was too soft to handle.  He approached a trained goldsmith who  advised him to  use 22-carat gold for this  purpose and this time he was successful and could make the ornaments.

    (a) What is the difference between 24-carat gold and 22-carat gold? 

      (b)Does gold corrode in saltwater?

       (c) Name the chemical which can dissolve gold.

       (d) Why is 22-carat gold used in making ornaments?