Wednesday, 30 August 2017

CLASS -8 
(Microorganism: Friend and Foe)
Multiple Choice Question- (1 Marks Each)
1.Bacteria are classified according to their:

i) Shape
ii) size

iii) color
iv) none of these
2.
The first antibiotic discovered was:







i) Penicillin
ii) Tetracycline

iii) Streptomycin
iv) Bacitracin
3.
Cholera is caused by:







i) vibrio cholera
ii) clostridium tetani iii) salmonella typhi
iv) none of these
4.
A common bacterial disease in plants is:






i) Citrus canker
ii) Rabies
iii) Polio
iv) All of these

5.A common food preservative is:







i) Benzoic acid
ii) Hydrochloric acid iii) Sulphuric acid

iv) Nitric acid
6.
An edible fungi is:







i) Mould
ii) Mushroom

iii) Algae
iv) None of these
7.
The smallest microorganism is:







i) Algae
ii) Protozoan

iii) Bacterium
iv) Virus

8.
Algae are:








i) Autotrophs ii) Parasites iii) Heterotrophy
iv) Saprophytes


9.
The microorganisms that play an important role in maintaining the balance of
nitrogen gas in the

atmosphere are:








i) Bacteria
ii) Algae
iii) Virus
iv) Protozoa


10. Which of these are added to dough to make it rise?
i) Yeast
ii) Algae
iii) garbage
iv) all of these
Fill in the blanks:- (1 Marks Each)
1.Microorganisms can be seen with the help of a ……………………..
2.Blue green algae fix ……………….. Directly from air to enhance fertility of soil.
3.Alcohol is produced with the help of ……………………….
4.Cholera is caused by …………………….
5.………………….. are non-green plants.
6.………………….. cause fermentation.
7.……………………….. and ………………………. Are diseases caused by fungi in humans.
8.A ………………….. found in the intestine of termite, help them to digest word cellulose.
9.…………………… only multiply in the body of a living organism.
10.……………….. is a fatal disease of humans as well as cattle.
Very Short Answer Question: (1 Marks Each)
1.Write the names of some diseases caused by virus.
2.What is the main ingredient of rava idlis and bhaturas.
3.What is fermentation?
4.Mention tow groups of Microorganisms on the basis of their functions?
5.Name some diseases caused by protozaans.
Short answer questions:
(2 Marks Each)
1.What are microorganisms?
2.How do microbes survive in adverse conditions?
3.How bacteria are useful to us?
4.What is virus?
5.What is fermentation? Where is it used?
6.Write two common bacterial disease of human and write preventive measures for it?
7.What is the role of yeast in baking industry ?
8.Write sum commercial use of microorganisms?
9.What is pasteurization of milk?
10.How do microorganisms spoil food?
Answer these question
(3 Marks Each)
1.
What are major groups of microorganisms?

2.
Draw any protozoa and Label its part.

3.
What are the antibiotics? What precautions one should take while taking them?
4.
How do bacteria help in increasing soil fertility? Explain.

5.
Classify the bacteria according to their shape.

6.
What are communicable diseases ? Explain with examples.

7.
What do you mean by food poisoning ?

8.
Explain how does a vaccine work?

9.
Describe the role of blue green alae and bacteria in fertility of soil ?
10.
Give one example of each.


i) an edible fungi
ii) antibiotic obtained from fungi
iii) a parasitic protozoan
iv) nitrogen fixing bacteria
v) a bacteria residing in intestines of man
vi) what is nitrogen cycle
Long answer questions.
(5 Marks Each)
1.Draw and explain the harmfull effects of bactria with Example.
2.What are food preservatives ? Explain some common food preservatives.
3.Explain cousative microorganisms, mode of transmission and preventive measure of the humand diseases like Tuberculosis, Measles, Chicken pox, Polio, Cholera, Typhoid, Hepatitis B and Maleria etc.
4.Explain Nitrogen Cycle with the help of Label Diagram?

5.Draw different types of fungi and write useful and harmful effect of fungi.
CLASS -10
CHEMISTRY WORKSHEET.

  CHEMISTRY                                                                                                                                                                                                                                                               30M    
1.       Name two organic acids.                                                                                                                 1M
2.       Which of the following reactions is not correct?
         Zn +CuSO4 → ZnSO4+ Cu
Ag +Cu (NO3)2 → Ag(NO3)2 +Cu
Fe+ CuSO4 → FeSO4+ Cu
2Mg + 2HCl→ MgCl2+ H2   
                                                                                                                                                         1M     
3.       Washing soda has the formula
Na2 CO3.7 H 2O 
Na2 CO3.10 H2 O
Na2 CO3.2 H 2O
Na2 CO3     
                                                                                                                                                                   1M
4.       Which of the following is evolved when Na2CO3 is heated?
a.       (a) CO2      (b) CO         (c) O2          (d) No                                                                                    1M
5.        Why does not an acid show any acidic behavior in the absence of water?        
                  2M
6.       Fresh milk has a pH of 6. What will be the PH value if milk changes into a curd Justify.           2M

7.       A housewife found that the cake prepared by her is hard and small in size. Which ingredient has she forgotten to add that would have made the cake fluffy. Give reason.  
                     2M
8.       What is water of crystallization. Name two hydrated salts.                                                        2M

9.       2. “Write the balanced chemical equations for the following and identify the type of reaction in each case:                                                                                                                                            3M
Barium chloride (aq) + potassium sulphate (aq) ---- Barium sulphate (s) + Potassium chloride (aq)
Zinc carbonate (s) ------- Zinc oxide (s) + Carbon dioxide (g)
Magnesium (s) + Hydrochloric acid (aq) ------- Magnesium chloride (aq) + Hydrogen(g)

a.       Corrosion
b.   rancidity                                                                                                                                   3M                              
11.   18.In the reaction MnO2 +4HCl--------- MnCl2 + 2H2O +Cl2
a.       Name the substance oxidised.
b.      Name the oxidising agent.
c.       Name the reducing agent and the substance reduced. 
                                   3M
12.   Give one example each of
Thermal decomposition
Electrolytic decomposition
Photo decomposition                                                                                                                       3M
13.   How is plaster of Paris chemically different from gypsum? How may these be inter converted? Write one use of plaster of Paris?                                                                                                  3M
14.   Why does a solution of sodium chloride conduct electricity while solid sodium chloride does  not?                                                                                                                                                              3M
With the help of chemical equations show that Al203 is an amphoteric oxide?
Shoe the formation of
NaCl , Na2O, MgCl2,AlCl3


CLASS-9
CHEMISTRY WORKSHEET

1.       The rate of evaporation decreases with                                                                                              1M
a.       (a) increase in humidity             (b) increase of temperature
b.      (c) increase in wind speed         (d) increase of surface area
2.       Arrange the following substances in increasing order of force of attraction between the particles.
a.       (i) milk         (ii) salt              (iii) oxygen                                                                                                                     1M
(a)    Conversion of solid into vapours without passing through the liquid state is called vaporization.
(b)   Conversion of vapours into solid without passing through the liquid state is called sublimation.
(c)    Conversion of vapours into solid without passing through the liquid state is called freezing.
(d)   Conversion of solid into liquid is called sublimation.                                                                                                                                                                                                                1M
4.       What is the value of boiling point of water on Kelvin scale of temperature?                                 1M
5.       On converting 25°C, 38°C and 66°C to kelvin scale, the correct sequence of temperature will be:
a.       298 K, 311 K and 339 K
b.      298 K, 300 K and 338 K
c.       273 K, 278 K and 543 K
d.      298 K, 310 K and 338 K                                                                                                                                                                                                     1M
6.       Convert:  
               (a) 27°C into kelvin scale                    (b) 500 K into Celsius scale                                                                                                                                                                                                    2M
7.        What is dry ice? Dry ice is compressed at high pressure. What happens when pressure is released?                                                                                                                                                                                                                                                                                2M
8.       Answer the following questions:
(a)    Why is ice at 273 K more effective in cooling than water at the same temperature?
(b)    Name the two gases which are supplied in compressed form in homes and hospitals.                                                                                                                                                                                                                                                                                             2M                                                          
9.        When a bottle of scent is opened in one corner of a room, it immediately spreads throughout the room. What property of matter is responsible for this observation? Explain                                                                                                                                                        3M
10.    Define (i) Latent heat of fusion and
                           (ii) Latent heat of vaporization.
                           (iii) Give suitable examples for (i) & (ii)                                                                                                                                                                                                                   3M
11.   What is Evaporation? Explain how the following factors affect the rate of evaporation of a liquid:
                                I.            Temperature of the liquid.                                                                                    3M
                              II.            Area of the exposed surface.
                            III.            Moisture in the surrounding air.
                            IV.            Increase in wind speed.