Chem Ms Set2 Delhi Xii 2008

8/12/2019 Chem Ms Set2 Delhi Xii 2008

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Marking SchemeChemistry

Delhi- SET (56/1/2)1 4 1

2 In primary battery the reaction occurs only once and after use over a period of time

becomes dead. Leclanche cell or Dry cell is an eample.

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# $.# Set 1 1

4 $.4 Set 1 1

% $.% Set 1 1

&.

'entane (2) 4 *dione

1

+. $.+ Set 1

1

,. $., Set 1 1

- aoult/s la0 states that for a solution of volatile liuids) the partial vapour pressure

of each component in the solution is directly proprtional to its mole fraction.

hen the solute(solvent interaction is 0eaker than those bet0een the solute(solute

and solvent(solvent molecules than solution sho0s positive deviation from aoults

la0 because the partial pressure of each component is greater.

e. miture of ethanol and acetoneorcarbondisulphide and acetone behave in this

manner.

hen the solute(solvent interaction is stronger than those bet0een the solute(solute

and solvent(solvent molecules than solution sho0s negative deviation from aoults

la0 and the partial vapour pressure of each component is lo0er.

e. miture of chloroform and acetone behave in this manner.

(Note: Explaination with suitable example of any one of the two.)

OR

3he etra pressure applied on the solution side that ust stops the flo0 of solvent to

solution through semi(permeable membrane is called osmotic pressure of thesolution.

5ere 6 is the osmotic pressure and is the gas constant.

3hus kno0ing the uantities 02) 3) 6 and 7 0e can calculate the molar mass of the

solute.

1

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1

1

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18

m9 1888 cm#L(1

c

9 8.824, S cm(1 1888 cm# L(1 9 24., S cm2

8.28 mol L(1 8.28 mol

m 9 124 Scm2mol(1

1

1

11 3he galvanic cell is depicted as:

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22 $.2# Set 1 #

2# $.22 Set 1 #

24 $.2& Set 1 #

2% $.2+ Set 1 #

2& $.2% Set 1 #

2+ $.24 Set 1 #

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dt

9 #


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2-

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(or any other suitable method)


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Chem Ms Set2 Delhi Xii 2008

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