DG KHAN BOARD 2017
PAPER CHEMISTRY PART-1
Time: 20 MM.  (Objective Part)

Marks: 17
Note: You have four choice for each objective type question as A, B, C and D. The choice which you think is correct; fill that circle in front of that question number. Use marker or pen to fill the circles. Cutting or filling two or more circles will result in zero mark in that question.

• Mass of one mole electrons is
  

1. 1.008 mg
   
2. 0.55 mg
   
3. 0.184 mg
   
4. 1.673 mg
   

• Cadmium has isotopes
  

1. 6
   
2. 8
   
3. 9
   
4. 11
   

• Gooch crucible is made of
  

1. Glass
   
2. Paper
   
3. Teflon
   
4. Porcelain
   

• The deviation of a gas from ideal behavior is maximum at
  

1. 0 - 10 °C and 5 atm.
   
2. - 10 °C and 2 atm.
   
3. 100 °C and 2 atm.
   
4. 0 °C and 2 atm.
   

• The temperature of natural plasma is about
  

1. 20000 °C
   
2. 10000 °C
   
3. 5000°C
   
4. 1000 °C
   

• Molecules of CO₂ in dry ice form the
  

1. Ionic crystals
   
2. Molecular crystals
   
3. Covalent crystals
   
4. Amorphous
   

• Forces of attraction between He atoms are
  

1. Hydrogen bonding
   
2. Debye forces
   
3. London forces
   
4. loo dipole forces
   

• Orbitals having same energy are called
  

1. Valence orbitals
   
2. S – orbitals
   
3. Outer orbitals
   
4. Degenerate orbitals

• Splitting of spectral lines in magnetic field is called
  
  

1. Zeeman effect
   
2. Stork effect
   
3. Photoelectric effect
   
4. Compton effect

• Number of bonds in nitrogen molecule are
  

1. One σ and one π 
   
2. One σ and two π 
   
3. Three sigma only
   
4. Three π only
   

• Percentage ionic character of HF is
  

1. 100 %
   
2. 80 % 
   
3. 43 %
   
4. 57 %
   

• One calorie is equal to
  

1. 0.4184 Joules
   
2. 41.84 Joules
   
3. 418.4 Joules
   
4. 4.184 Joules
   

• An excess of aqueous silver nitrate is added to aqueous barium chloride. Precipitates of silver chloride removed by filtration. What are the main ions present in the filtrate?
  

1. Ag+ and NO₃^- only
   
2. Ag- Ba₂⁺ and NO₃^-
   
3. Ba₂+and NO₃^- only
   
4. Ba₂⁺ , NO₃^- and C1₃^-1
   

• pH of soft drinks at 25 °C is about
  

1. 3.0
   
2. 11.0
   
3. 1.0
   
4. 7.0
   

• An aqueous solution of ethanol may have vapor pressure
  

1. equal to that of water
   
2. equal to that of ethanol
   
3. more than that of water
   
4. less than that of water

• Stronger the oxidizing agent, greater is the 
  

1. Oxidation potential
   
2. Redox potential
   
3. E.M.F. of cell
   
4. Reduction potential
   

• With increase of 10 °C temperature the rate of reaction doubles. This increase in rate of reaction is due to
  

1. Increase in number of effective collisions
   
2. Decrease in activation energy of reaction
   
3. Decrease in the number of effective collisions
   
4. No change in number of collisions

DG KHAN BOARD 2017
PAPER CHEMISTRY PART-1
Time: 3:10 Hours (Subjective Part)   Marks: 83
Section-I

2. Attempt any EIGHT short questions.

1. Define molecular formula. Write down the relationship between molecular formula and empirical formula
   
2. Calculate the number of oxygen atoms in 10.037 g of CuSO₄.5H₂O Atomic mass of Cu = 63, H=1 .O=16
   
3. Define molar volume. Give at least one example
   
4. Write down the uses of chromatography
   
5. Write methods of drying of crystals
   
6. Write down four properties of a good solvent
   
7. How absolute zero is explained by drawing graph?
   
8. State Avogadro's law and also give one example
   
9. Why deep sea divers take oxygen mixed with an inert gas like He?
   
10. Prove Kp = Kc (RT) Δn
    
11. State Lechatlier's Principle. What happens when pressure is increased on the reaction N₂ + 3H₂= 2NH₃
    
12. How buffer solutions are prepared? Discuss two methods

3. Attempt any EIGHT short questions.

• Define Anisotropy and Allotropy
  
• What are dipole - dipole forces. How they affect thermodynamic properties of substances
  
• Define vapor pressure. Name the factors which effect on vapor pressure of a liquid
  
• Write four properties of Metallic crystals
  
• Slate Pauli’s Exclusion principle
  
• Why the positive rays are also called canal rays?
  
• What is the origin of line spectrum?
  
• Write down electronic configuration of 21Sc 35Br
  
• Define Molarity. Give its mathematical expression
  
• Define Hydration energy of ion
  
• What are secondary cells? Give their two examples
  
• Write reactions for the electrolysis of fused sodium chloride

4. Attempt any SIX short questions.

• What is "Octet rule"? Give two examples of the compounds which do not obey Octet rule
  
• How Sigma and pi bonds are formed?
  
• Explain the structure of CH₄ on the basis of sp3 hybridization
  
• Define "Dipole moment Give its various units
  
• Define "System" and Surroundings"
  
• The burning of candle is a spontaneous process. Justify it
  
• What is Zero order reaction"? Give one example
  
• Differentiate between" Instantaneous rate "and" average rate” of a reaction
  
• What is "Autocatalysis"? Give one example

SECTION-II

Attempt any THREE questions.

5.

1. A well-known ideal gas is enclosed in a container having volume 500 cm3 at S.T.P. Its mass comes out to be 0.72 g. What is the molar mass of this gas?
   
2. What are molecular solids? Write down properties of molecular solids

6.

1. Prove PV = nRT. Give value of R in SI unit
   
2. Give postulates of Bohr's atomic model

7.

1. Write main postulates of molecular orbital theory
   
2. Explain enthalpy of a reaction and prove H = qp
   

8.

1. Ca(OH)₂ is a sparingly soluble compound. Its solubility product is 6.5 x 10-6. Calculate the solubility of Ca(OH)₂
   
2. Describe the galvanic cell explaining the functions of electrodes and salt bridge

9.

1. Differentiate between Hydration and Hydrolysis with examples
   
2. Describe half-life method for determination of order of reaction