Chemistry
Fereral Board 2016
Inter Part-1
Time: 25Min
Objective Part
Marks =17
SECTION-
Note: Section A is compulsory. All parts of this section are to be answered on the question paper itself. It should be completed in the first 25 minutes and handed over to the Centre Superintendent. Deleting/overwriting is not allowed. Do not use lead pencil. 

Question#1
Circle the correct option i.e. A/B/C/D. Each part carried one mark.

• Born-Haber cycle is a special application of:
  
  (a) Hess’s law
  (b) Rate law
  (c) Boyle’s law
  (d) Henery’s law

• Oxidation number of ‘Min” in KMnO₄ is:.
  
  (a) +6
  (b) +5
  (c) +8
  (d) +7

• The relative atomic mass of chlorine (Cl) is 35.5 amu. The mass in grams of 0.5 moles of chorine gas is.
  
  (a) 35.5 grams
  (b) 18.75 grams
  (c) 142 grams
  (d) 71 grams

• Charge on one kilogram electron is
  
  (a) 1.7588 x 10 ¹¹C
  (b) 1.7588 x10 ¹¹C
  (c) 1.6 x 10^-19 C
  (d) 6.67 x 10 ³⁴C

• Which are not produce by neutrons decay?.
  
  (a) Electron
  (b) Neutrino
  (c) Positron
  (d) Proton

• According to VSEPR theory the shape of AB₃E type molecule is.
  
  (a) Triangular pyramidal
  (b) London forces
  (c) Bond length
  (d) Bond order

• Which of the following gas will diffuse more rapidly at STP?.
  
  (a) Oxygen gas
  (b) Carbon dioxide gas
  (c) Chlorine gas
  (d) Methane gas

• Bond energy is independent of:
  
  (a) Atomic size
  (b) London forces
  (c) Bond length
  (d) Bond order

• Pressure exerted by a real gas is always less than that of an ideal gas at same condition due to:
  
  (a) Intermolecular forces of attraction
  (b) Zero kinetic energy of molecule
  (c) Zero kinetic energy of molecule
  (d) Large empty spaces

• Distillation under reduced pressure is called:.
  
  (a) Steam distillation
  (b) Destructive distillation
  (c) Fractional distillation
  (d) Vacuum distillation

• Existence of CaCO₃ is in trigonal
  
  (a) Isomorphism
  (b) Anisotropy
  (c) Polymorphism
  (d) Allotropy

• At equilibrium state:
  
  (a) Concentration of products become zero
  (b) Concentration of reactants and products becomes constant
  (c) Concentration of reactants and products become equal
  (d) Concentration of reactants becomes zero

• If a reaction does not proceed appreciably in forward drection it shows.
  
  (a) Zero K_c value
  (b) Very large K_c value
  (c) Very large K_c value
  (d) Very small K_c value

• Which one of the following is not a Lewis Base?
  
  (a) NF₃ 
  (b) BF₃
  (c) NH₃
  (d) H₂O

• For an endothermic reaction the energy of product is.
  
  (a) Equal to that of reactant
  (b) Equal to the energy of activation
  (c) Higher than that of reactants
  (d) Lower than that of reactants

• Red blood cells are not affected by osmosis if they are placed in.
  
  (a) 95% on NaCl solution
  (b) 0.95% of NaCl solution
  (c) Pure water
  (d) 9.5% of NaCl solution

• Depression of freezing point for one molal solution of a non- (volatile, non-electrolyte solute is called:
  
  (a) Cryoscopic constant
  (b) Ebullioscopic constant
  (c) Rate constant
  (d) Equilibrium constant

CHEMISTRY HSSC-I
(Revised syllabus)
SECTION — B
(Marks 42)

Attempt any FOURTEEN parts. The answer to each part should not exceed 5 to 6 lines. (14x3 = 42)
Question#2

•  (i) How many covalent bonds are present in 34 grams of ammonia (NH₃)? [At masses N=14 H=1] 03
•  (ii) Using Bohr's equation calculate the distance travelled by an electron of a Hydrogen Atom when it jumps from 1st to 2nd orbit 03
•  (iii) Write three properties of canal rays 03
•  (iv) Describe the shape of following molecules by using VSEPR concept 03
  (a) PH₃ 
  (b) H₂ S
•  Explain sigma bond and Pi bond giving one example in each case 03
•  Hydrogen gas collected at 6 ⁰C and 765  mmHg occupied 35cm³ volume Calculate the volume of Hydrogen gas at STP 03
•  What is plasma? Give its four properties 01 + 02
•  What is vapour pressure of a liquid? Discuss the effect of temperature and
• Intermolecular forces on the vapour pressure 03
• Give two definitions of Lattice Energy with an example in each case 03
•  Write k_e expression for the following reactions 03
  (a) FeO (s) + CO (g)⇌Fe (s) + CO₂ (g)
  (b) P4 (s) + 5O₂⇌ (g)P₄O₁₀ (S)
  (c) CH₄ (g) + 4CL₂⇌(g) CCL₄ (L) + HCL (g)
• Define solubility product and write K, expression for a sparingly soluble salt A, B, 01+ 02
• Calculate pH of a Buffer solution containing O 1 M acetic acid (CH₃COOH) and 1 O M Sodium acetate (CH₃COONa) The pk_a for acetic acid is 4 /6 . 03
• Use the concept of Hydrolysis to explain why aqueous solutions of some salts are acidic basic or neutral 03
• Define the following 03
  (a) Average rate of reaction
  (b) Instantaneous rate of reaction
  (c) Order of reaction
• The action given below is first order in H₂ and malt order in Br₂  03
  H₂ (g) + Br₂ (g)→2HBr (g)
  Write rate equation (rate law) of the reaction and deduce overall order of reaction
• Calculate the mass percent of a solution containing 10 grams of sugar and 100 grams of water 03
• Using Raoult's law to prove that the Relative Lowering of vapour pressure is equal to the mole fraction of the non-volatile, non-electrolyte solute 03
• State and explain Hess's law using a general reaction
• Balance the following Redox equation by using oxidation number method  03
  NaClO₂+Cl₂→NaCI+ClO₂

SECTION - C
(Marks 26)
Note: Attempt any TWO questions. All questions carry equal marks. (2 x 13 = 26)

Question#3

(a) Draw Molecular orbital diagram of 0, and explain its paramagnetic behavior 04
(b) What mass of silver chloride be produced by reacting 120 grams of silver nitrate wit 52 grams of sodium chloride
 AgNO₃ + NaCI→ AgCI + NaNO (At masses Ag = 108. N = 14 Na = 23, CI = 35. 5 O = 16) 05
(c) Derive the Ideal Gas Equation and determine the value of ideal Gas Constant (R) using S I units 04

Question#4

(a) State and explain the Law of mass action and derive the equilibrium constant (Kc ) Expression for a general reaction 02 + 03
(b) In an acid-base titration 25 cm of 0 12M solution of NaOH is neutralized by 30cm' of HCI solution Calculate the concentration and strength of HCI solution 04
(c) Discuss the effect of change in concentration of reactants and the change In surface area of the reactants on the rate of reaction 02 + 02

Question#5
(a) Define modality of a solution and calculate the molality of a solution prepared by mixing 1 gram of Ethanol (C₂H₂OH) with 100 grams of water [At masses C = 12, O = 16. H=1)  (01+03)
(b) Derive an expression to calculate the molar mass of a non-volatile non- electrolyte Solute by the lowering of vapour pressure 04
(c) What is standard Enthalpy of atomization? Give an example 01 + 01
(d) Discuss the Construction of standard Hydrogen Electrode using its labeled Diagram 03