FUNCTIONING OF NEPHRON

NEPHRON

COMPOSITION OF ALLOYS

BRONZE  :  COPPER [ 88 %] & TIN [ 12 % ]

BRASS     :  COPPER [ 70 %] & ZINC [ 30 % ]

SOLDER  :   LEAD [ 40 %] & TIN [ 60 % ]
Amalgam is an alloy containing mercury [Hg].[Hydrargyrum]

X SA I TEST CHEM REACTION, ELECTRICITY, CONTROL & COORDINATION

X TEST – SCIENCE- CHEMICAL REACTION, ELECTRICITY, CONTROL & COORDINATION               M.M: 40

1.       [1]Define  electric  circuit.   Distinguish between open  and  closed  circuit.                                       

2.       [1] What  is meant by skeletal  equation ?                                                                                                

3.       [2]What  is a redox  reaction?   Write  down a chemical  equation representing it.           

4.       [3]Ram has  met  with  an accident after  that  he lost the  capacity to                                                

(i)      walk  in straight line         (ii)     smell  anything           (iii)    does  not feel full after  eating

Which  part  of brain  is damaged in each  case.

5.       [3]Name  the hormone secreted by ovary,  testes  and  adrenal glands.  Write  a function of each  hormone.

6.       [1,1] (a)     What  material is used  in making the filament of an electric  bulb  ?                                  

                   (b)     Name  the characteristics which  make  it suitable for this.

7.       [2] Differentiate overloading and  short  circuiting.                                                                        

8.       [2] Mention the components of the transport system in highly  organized plants.  State the functions of these  components.

9.       [2] What  is meant by thermal decomposition reaction ?  Explain  with  an example.                 

10.    [2] An aluminium can is used  to store Ferrous sulphate solution. It is observed that in few days  holes  appeared in the can.   Explain  the observation and  write  chemical  equation to support your  answer.

11.    [3] A piece of wire of resistance 20Wis drawn out so that its length  is increased to twice its original length.  Calculate the resistance of the wire  in the new  situation.

12.    [3] (a)     What  is the total  resistance of n resistors each of resistance ‘R’ connected in :             

                (i)      Series  (ii)     Parallel

13.     [3] Name  the hormone secreted by thyroid gland.  Write its function.  Why is it important for us to have  iodised salt in our  diet ?

14.    [3]How  does  feed-back mechanism regulate the hormone secretion ?                                         

15.    [3] Give  three  differences between displacement and  double displacement reaction.               

16.    [5]Four  metals  A,B,C and  D are inturn added to the following solutions one by one.   The observations made are tabulated below.

Metal	Iron (II) sulphate	Copper (II) Sulphate	Zinc sulphate	Silver nitrate
A	No reaction	Displacement	-	-
B	Displacement	-	No reaction	-
C	No reaction	No reaction	No reaction	Displacement
D	No reaction	No reaction	No reaction	No reaction

Answer the following questions based  on the above  information.

 (i)     Which  is the most  active  metal  and  why  ?

(ii)     What  would be observed if B is added to a solution of copper sulphate and  why.

(iii)    Arrange the metals  A,B,C and  D in order of increasing reactivity.

(iv)    Container of which  metal  can  be used  to store  both  Zinc sulphate solution and silver nitrate solution.

(v)     Which  of the above  solutions can be easily stored in a container made up  of any of these  metals.

X SA I TEST CHEMISTRY

TEST– X /SCIENCE [CHEMISTRY]

TIME:90Min.                                                                                                                                                                               M.M. 60

1.       [1]Name two metal which has low melting point.

2.       [1]Name a non-metal which is extremely hard.

3.       [1]Explain why, the surface of some metals acquires a dull appearance when exposed to air for a long time.

4.       [1]What happens when calcium reacts with water ? Write the equation of the reaction of calcium with

5.       [1]What is aqua-regia ? Can it dissolve gold metals?

6.       [2]Arrange the following metals in order of their chemical reactivity, placing the most reactive first :Magnesium, Copper, Iron, Sodium, Zinc, Lead, Calcium

7.       [2]What will happen if a strip of zinc is immersed in a solution of copper sulphate.

8.       [2]A copper coin is kept immersed in a solution of silver nitrate for some time. What will happen to the coin and the colour of the solution. Give reaction

9.       [2]Name one metal which displaces copper from copper sulphate solution and one which does not. Give reaction

10.    [2]What type of oxide are formed when non-metals combine with oxygen ? Explain with the help of an example. Is it basic or acidic? Give appropriate reaction to justify.

11.    [2]Explain why metals do not liberate hydrogen gas with dilute nitric acid. Which metals do so. Give reaction

12.    [2]Give reason for the following :

Carbonate and Sulphide ores are usually converted into oxides during the process of extraction.

13.    [2]Explain giving one example, how highly reactive metals ( which are high up in the reactivity series ) are expected.

14.    [2]How is manganese extracted from manganese dioxide MnO₂ ? Explain with the help of an equation.

15.    [2]What is a thermit reaction ? Explain with the help of an equation. State one use of this reaction.

16.    [2]What  is the brown coloured gas evolved when lead nitrate crystals  are heated in  a dry test tube  ?

17.    [2]On mixing  solutions of lead  nitrate and  potassium iodide in a test tube.                                  

(a)     Write  the chemical  equation involved in the balanced form.

(b)     What  is the colour  of the precipitate ?  Name  the precipitate.

18.     [1,1,3]What is chlor-alkali process? Write its products and their uses. ( 3 each)

19.    [3]What are amphoteric oxide ? Give examples of two amphoteric oxide.Show their reactions.( All 4

reactions)

20.    [3]Define the terms ; (i) mineral, (ii) ore, and (iii) gangue.

21.    [3]A zinc ore on heating in air forms sulphur dioxide. Describe briefly any two stages involved in the

conversion of this concentrated ore into zinc metal.

22.    [3]Compounds like alcohol and glucose also contain hydrogen but are not characterized as acids. Describe an activity to prove it.

23.    [3]Write following reactions

(a)                An acid with Metal Carbonate & Metal bi-carbonate

(b)                How to identify the gas evolved by above reactions. Write equation.

24.    [4]Write about followings:

(a)                Do metals reacts with base to evolve hydrogen gas. If yes write reaction.

(b)                What is hydronium ion ?

(c)                Do basic solutions also have H+(aq) ions? If yes ,then are these basic?

25.    [4] (a)     What  are  redox  reactions ?                                                                                                       

(b)     Why  the  reaction between Manganese dioxide and  Hydrochloric acid  is redox reaction ?

(c)     Identify the substance oxidised and  the substance reduced in the above  reaction.

26.    [5] (a)     Name  the components of the alloys  steel and  stainless steel.

(b)     Why gold  is alloyed with  copper ?

(c)     Name  a metal  which & give reaction

(i)      will react  vigorously with  cold water

(ii)     will react  with  only  hot  water

(iii)    will only  react   with   steam