Rajasthan Board Class 12 Question Paper 2020 Agriculture Chemistry

 Roll No.

No. of Questions – 30
No. of Printed Pages – 7 SS-38-Ag. Chem.

   (AGRICULTURE CHEMISTRY)
  , 2020
 3¼ 
 56

     

GENERAL INSTRUCTIONS TO THE EXAMINEES :

(1)    -     

Candidate must write first his / her Roll No. on the question paper compulsorily.

(2)      

All the questions are compulsory.

(3)       -    

Write the answer to each question in the given answer-book only.

SS-38-Ag. Chem. [ Turn over

2

(4)      ,         

For questions having more than one part, the answers to those parts are to be written

together in continuity.

(5) -    
       //      

    

If there is any error / difference / contradiction in Hindi & English versions of the

question paper, the question of Hindi version should be treated valid.

(6)      

 1 – 13 1

 14 – 24 2

 25 – 27 3

 28 – 30 4

Section Q. Nos. Marks per question

A 1 – 13 1

B 14 – 24 2

C 25 – 27 3

D 28 – 30 4

(7)   28, 29  30     

Question Nos. 28, 29 and 30 have internal choices.

3

 – 
SECTION – A

1.            ?
How much percentage of silica generally found in basic igneous rocks ? 1

2.         
Write the name of any two species of azotobactor. 1

3. “ ”   ?

What is “Tyndal Effect” ? 1

4.       
Write the unit of cation exchange capacity. 1

5.         ..   
Write the suitable pH value of soil for wheat crop. 1

6.       
Write the chemical formula of Lime stone. 1

7.            
Write the name of any two macro nutrients for plants. 1

8.                 
SS-38-Ag. Chem. [ Turn over

4
Write the name of the rock formed by the effect of heat and pressure on igneous and
sedimentary rocks. 1

9. ‘’    

Define composting. 1

10.       
Write the cation exchange capacity of humus. 1

11.                  
Write the name of any two indicator plants that indicate nitrogen deficiency in plants. 1

12.              
Explain the relationship between the quantity of clay and cation exchange capacity in
soil. 1

13.                
Write the name of chemical which use to check the starch adulteration in milk. 1

 - 
SECTION – B

14. -         
Write the method of seed treatment of green gram by bio-fertilizer. 2

15.           
Write any four symptoms of phosphorous deficiency in crops. 4×½=2

5

16.           
Define lipids. Write two biological functions of it. 1+½+½=2

17.        
Write a short note on water soluble vitamin. 2

18.               
  
Explain the waiting period of pesticides after its application. Write the waiting period of
monocrotophos and cypermethrin. 1+½+½=2

19.           
Describe the four measures to control the air pollution. ½+½+½+½=2

20. ‘’         

Draw a labelled diagram of the row structure of kaolinite group. 2

21.            
Draw a labelled diagram of any two parts of cream separator bowl. 1+1=2

22.         
Display the classification of rocks by line diagram. 1+1=2

23.         
Explain the Carbon : Nitrogen Ratio in soil. 2

24.  ..           

SS-38-Ag. Chem. [ Turn over

6
Describe any four factors which affect soil pH. 4×½=2

 – 
SECTION – C

25.                  
Distinguish between active acidity and exchange acidity. Write any four causes of acidic
soil formation. 1+2=3

26.                 ?     
 
Which test to be done to detect adulteration of water in milk ? Describe the application
method. 1+2=3

27.           -         
  
Write the name of any one bio-fertilizer used in paddy crop. Describe the method of
application. 1+2=3

 – 
SECTION – D

28.     ?    

   ?    
What is monosaccharides ? Describe in detail. 1+3=4
OR
What is preservative ? Describe in detail.

7

29.             

            
Explain Air pollution. Describe any three sources of it. 1+3=4
OR
Explain soil pollution. Describe any three sources of it.

30.     ,   ,         
    

    ,   ,          
   
Describe the composition, any two properties, soil reaction and any four effects on crops
of calcium ammonium nitrate. 1+1+1+1=4
OR
Describe the composition, any two properties, soil reaction and any four effects on crops
of sulphate of potash.
____________

SS-38-Ag. Chem. [ Turn over

8