TEST PAPER 10 - UNITS 4,5 - 50 MARKS

There are 26 questions in all and time limit is 90 minutes.

SECTION - A : CHOOSE APPROPRIATE ALTERNATIVE : [1 mark each, Total marks 7]

1. In p^H scale, the base of the logarithm of molar concentration of H₃O⁺ ion is ______.
   
   
   
   1. 10
   2. 20
   3. 50
   4. 100
      
   
   
2. What is used as an antacid ?
   
   
   
   1. Na₂CO₃
   2. NaHCO₃
   3. NaCl
   4. NaOH
      
   
   
3. ______ is an ore of calcium.
   
   
   
   1. Magnetite
   2. Siderite
   3. Malachite
   4. Gypsum
      
   
   
4. ______ is a poor conducting metal for heat.
   
   
   
   1. Copper
   2. Silver
   3. Aluminium
   4. Lead
      
   
   
5. There are ______ nonmetallic elements.
   
   
   
   1. 20
   2. 22
   3. 24
   4. 25
      
   
   
6. ______ have fruity smell.
   
   
   
   1. Alcohols
   2. Organic acids
   3. Esters
   4. Ketones
      
   
   
7. Which of the following is artificial rubber ?
   
   
   
   1. Isoprene
   2. Chloroprene
   3. Neoprene
   4. TEFLON
      
   
   
   
   

   SECTION - B : ANSWER IN SHORT : [1 mark each, Total marks 7]
   

8. What is used as catalyst in the preparation of vegetable ghee ?
9. Give two examples of irreversible reaction.
10. What is the full form of RCC ?
11. Write the chemical equation for the preparation of quick lime.
12. Why are metals like sodium, pottasium and aluminium not available in free state in nature ?
13. Why is ammonia not collected by downward displacement of water ?
14. Write the chemical equation for the combustion of ethanol.
    
    

    SECTION - C : ANSWER IN BRIEF : [2 marks each, Total marks 12]
    

15. Mention the criteria for chemical equilibrium.
16. Describe the preparation of bleaching powder giving chemical reaction.  OR   Mention four uses of washing soda.
17. Give chemical equations : (i) when iron reacts with steam (ii) when magnesium reacts with hot boiling water.  OR   Write the chemical equations involved in Bayer's process.
18. Describe Frasch process to obtain sulphur(no diagram).
19. Describe : Vulcanisation of rubber.
20. Describe harmful effects of ethanol.
    
    

    SECTION - D : ANSWER THE FOLLOWING : [3 marks each, Total marks 9]
    

21. Write the chemical formula of ordinary glass and describe its manufacture.
22. Write three chemical properties of sulphur dioxide.
23. Describe preparation of methanal from methanol, mention two properties and two uses of methanal.  OR   Write an introductory note on carbonyl compounds.
    
    

    SECTION - E : ANSWER IN DETAIL : [5 marks each, Total marks 15]
    

24. Explain the concept of dynamic nature of chemical equilibrium giving example.
25. What is concentration of ore ? Describe the process used to concentrate a sulphide ore.  OR   Describe refining of metals by elecrolysis giving example.
26. Describe preparation of hydrogen in laboratory with neat diagram.