Chemistry
Lahore Board 2015
Inter Part-1
Group - 1
Time: 20 Min Objective Type Marks = 17
Note: Four possible answers A, B, C and D to each question are given. The choice which you think is correct, fill that circle in front of that question with Marker or Pen ink in the answer-book. Cutting or filling two or more circles will result in zero mark in that question.

• Which of the following has zero dipole moment:
  
  (A) NH₃
  (B) BF₃
  (C) H₂O
  (D) H₂S
• An excess of aqueous AgNO₃ is added to aqueous BaCl₂ The precipitate is removed off. The filtrate contains:
  
  (A) Ag⁺ and NO₃^-ions
  (B) Ag⁺ Ba⁺² and NO₃^-ions
  (C) Ba⁺² and NO₃^-only
  (D) Ba⁺², NO₃^- and Cl^-ions
  
  
•  In dry ice CO₂ molecules form:
  
  (A) Ionic crystals
  (B) Covalent crystals
  (C) Molecular crystals
  (D) Any type of crystals
  
  
• Molarity of pure water is:
  
  (A) 1
  (B) 18
  (C) 6
  (D) 55
  
  
• Orbitals having same energy are called:
  
  (A) Hybrid orbitals
  (B) Valence orbitals
  (C) Degenerate orbitals
  (D) d-orbitals
  
  
• In H₂SO₄ the oxidation number of S is:
  
  (A) +2
  (B) +6
  (C) +8
  (D) +4
  
  
•  Pressure remaining constant at which temperature the volume of a gas will become twice of what it is at 0 ^◦C:
  
  (A) 546 ^◦C
  (B) 200 ^◦C
  (C) 546 K
  (D) 273 K
  
  
• Volume occupied by 1.4 g of N₂ at S.T.P. is:
  
  (A) 2.24 dm³
  (B) 22.4 dm³
  (C) 1.12 dm³
  (D) 112.0 cm³
  
  
• Which of the following has highest bond energy?
  
  (A) HI
  (B) HBr
  (C) HCl
  (D) HF
  
  
• The pH of 10^-3 molar H₂SO₄ solution is:
  
  (A) 3.0
  (B) 2.7
  (C) 2.0
  (D) 1.5
  
  
•  When 6 d orbital is complete the entering electron foes to:
  
  (A) 7 f
  (B) 7 s
  (C) 7 p
  (D) 7 d
  
  
• At what external pressure the boiling point of water will be 110^◦C:
  
  (A) Any value of pressure
  (B) 765 torr
  (C) Between 200 torr and 760 torr
  (D) Between 760 torr and 1200 torr
  
  
• In solvent extraction the law applied is:
  
  (A) Law of mass action
  (B) Distribution law
  (C) Coulomb’s law
  (D) Boyle’s law
  
  
• The volume of one mole CO₂ is maximum at:
  
  (A) S.T.P
  (B) 127^◦ and 1 atm.
  (C) 0^◦C and 2 atm
  (D) 273^◦C and 2 atm.
  
  
• One calorie is equal to:
  
  (A) 4.184 J
  (B) 0.4184 J
  (C) 41.84 J
  (D) 418.4 J
  
  
• The rate of reaction:
  
  (A) Increases as the reaction proceeds
  (B) Decreases as the reaction proceeds
  (C) Remains the same as reaction proceeds
  (D) May decrease or increase as the reaction proceeds
  
  
• The number of carbon atoms in 22.0 g of CO₂ is:
  
  (A) 3.01 x 10²³
  (B) 6.02 x 10²³
  (C) 3.01 x 10²²
  (D) 60.2 x 10²²

Chemistry
Lahore Board 2015
Inter Part-1
Group-1
Time: 3.10 hrs
Essay Type
Marks = 83

SECTION-I

2.Write short answers to any EIGHT (8) questions: (16)

• Actual yield is usually less than the theoretical yield.
• A compound may have same empirical as well as molecular formula. Justify.
• What is Avogadro’s numbers? Give equation to relate the Avogadro’s number and mass of an element.
• Define sublimation. What type of a substance can be purified by this technique?
• What is difference between qualitative analysis and quantitative analyses?
• Write down the faulty postulates of kinetic molecular theory of gases.
• What is plasma state? How is plasma formed at high temperature?
• Explain the term enthalpy of atomization.
• What is lattice energy? Give an example.
• How the direction of reversible reaction at any instant can be determined by k_c value?
• State Le-Chatelier’s principle and discuss the effect of change in concentration of a product on reversible reaction.\
• A weak acid has strong conjugate base. Justify.

3. Write short answers to any Eight (8) questions: (16)

• Why different liquids evaporate at different rates even at the same temperature?
• How the liquid crystals help in the detection of the blockage in veins and arteries?
• Why ionic crystals are highly brittle?
• What is the relationship between polymorphism and allotropy?
• What are defects in Rutherford’s atomic model?
• Justify that the distance gaps between different orbitals go on increasing from the lower to higher orbits.
• Define Zeeman’s effect and Stark effect.
• State Pauli Exclusion Principle and Hund’s rule.
• How the nature of a chemical bond is predicted with the help of electronegativity values of two bonded atoms?
• No bond in chemistry is 100% ionic. Justify it.
• The bond angles of H₂O and NH₃ are not 109.5^◦ like that of CH₄ although oxygen and nitrogen atoms are SP³- hybridized. Why?
• Wxplain the term bond order.

4. Write shore answers to any SIX (6) questions: (12) 

• Why the NACl and KNO₃ are used to lower the melting point of ice?
• Define upper consulate temperature with example.
• Define hydrolysis with example.
• Voltaic cell is reversible cell, State.
• How fuel cells produce electricity?
• Calculate oxidation number of chromium in CrCl₃.
• The sum of the coefficients of a balanced chemical equation is not necessarily important to give the order of reaction justify.
• Define homogenous catalysis, give two examples.
• What is catalytic poisoning? Give two examples.

SECTION-II

Note: Attempt any THREE questions.

Question#5.

(a) What are molecular solids? Give examples and explain their properties. (4)
(b) A mixture of two liquids, hydrazine N₂H₄ and N₂H₄ are used in rockets. They produce N₂ and water vapours. How many grams of N₂ gas will be formed by reacting 100 g of N₂H₄ and 200 g of N₂H₄: (2N₂H₄ + N₂O₄ 4H₂O + 3N₂ .(4)

Question#6

(a) How volume and pressure were corrected by Vander Waals? (4)
(b) Discuss magnetic and spin quantum number. (4)

Question#7

(a) Explain important points of molecular orbital theory and draw structure of nitrogen (N₂) molecule according to this theory. (4)
(b) Define the following with example:
(i) System. (ii) Non-spontaneous reactions.
(iii) Surrounding. (iv)Endothermic reactions.

Question#8

(a) Explain any four characteristics of a catalyst. (4)
(b) Benzoic acid C₆H₅COOH is a weak mono-basic acid (Ka = 6.4 x 10^-5 mol dm^-3). What is the PH of solution containing 7.2 g of sodium benzoate in one dm³ of 0.02 mole dm^-3 benzoic acid?

Question#9

(a) Describe one method to determine the boiling point elevation of solution. (4)
(b) Explain the construction and working of fuel cell.

SECTIONS-III (Practical Part)

Note: (i) Attempt any THREE questions.

(ii) Write down material required, diagram and procedure for Part A and B
(iii)Write down standard solution, chemical equation with mole ratio, indicator with end point, procedure and supposed reading with calculation for Part C, D, and E. (1, 1, 1, 1, 1)

1. Separate a mixture of inks by paper chromatography.(5)
2. Purify benzoic acid by water solution.(5)
3. 4 g of impure KOH are dissolved in 500 cm³ solution Find out %age purity.(5)
4. 5 g of impure KMnO₄ are dissolved per dm³ solution. Find out the %age purity of the sample.(5)
5. 7 g of impure sodium thiosulphate have been dissolved in 250 cm³ solution. Find out %age purity of the sample. (5)

Chemistry
Lahore Board 2015
Inter Part-I
Group-II
Time: 20 Min.
Objective Type
Marks = 17
Note: Four possible answers A, B, C and D to each question are given. The choice which you think is correct; fill that circle in front of that question with Marker or Pen ink in the answer-book. Cutting or filling two or more  circles will result in zero mark in that question.

• The number of bonds in oxygen molecule is:
  
  (A) One σ and one тт
  (B) One σ and two тт
  (C) Three sigma only
  (D) Two sigma only
  
  
• When 50% reactants in a reversible reaction are converted into a product, the value of equilibrium constant k_c is:
  
  (A) 2
  (B) 1
  (C) 3
  (D) 4
  
  
• Pressure remaining constant, at which temperature the volume of a gas will become twice of what it is at 0◦C:
  
  (A) 546◦C
  (B) 200◦C
  (C) 546 K
  (D) 273 K
  
  
• Molarity of pure water is:
  
  (A) 1
  (B) 18
  (C) 55.5
  (D) 6
  
  
•  The wave number of the light emitted by a certain is 2 x 10⁶ m^-1. The wavelength of this light will be:
  
  (A) 500 nm
  (B) 500 m
  (C) 200 nm
  (D) 5 x 10⁷ m
  
  
• The oxidation number of Cℓ in HCℓO₄ is:
  
  (A) +2
  (B) +3
  (C) +5
  (D) +7
  
  
• The boiling point of water at the top of Mount Everest is:
  
  (A) 59◦C
  (B) 69◦C
  (C) 83◦ C
  (D) 75◦C
  
  
• 7 g of Aℓ will react completely with how much mass of O₂ to produce Aℓ₂O₃
  
  (A) 0.8 g of oxygen
  (B) 1.6 g of oxygen
  (C) 3.2 g of oxygen
  (D) 2.4 g of oxygen
  
  
• For a given process, the heat changes at constant pressure (q_p) and at constant volume (q_v) are related to each other:
  (A) q_p= q_v
  (B) q_p<q_v
  (C) q_p > q_v
  (D) q_v =q_v /2
  
  
• The pH of 10^-3 mol dm^-3 of an aqueous solution of H₂SO₄ is:
  
  (A) 3.0
  (B) 2.7
  (C) 2.0
  (D) 1.5
  
  
• Bohr model of atom is contradicted by:
  
  (A) Plank’s quantum theory
  (B) Dual nature of matter
  (C) Heisenberg’s uncertainty principle
  (D) all of these
  
  
• The substance used for decolourization of undesirable colour in a crystalline Substance is:
  
  (A) H₂SO₄
  (B) Silica gel
  (C) NaNO₃
  (D) Animal charcoal
  
  
• Which of the following is a pseudosolid:
  
  (A) NaBr
  (B) Glass
  (C) AgNO₃
  (D) Naphthalein
  
  
• Equal masses of methance and oxygen are mixed in an empty container at 25◦C. The fraction of total pressure exerted by oxygen is:
  
  (A) 1/3
  (B) 8/9
  (C) 1/9
  (D) 16/17
  
  
• Which of the hydrolysis halides has the highest percentage of ionic character:
  
  (A) HF
  (B) HCℓ
  (C) HBr
  (D) Hl
  
  
• The enzyme used for hydrolysis of urea is:
  
  (A) Invertase
  (B) Urease
  (C) Lipase
  (D) Zymase
  
  
• The mass of two moles of electrons is :
  
  (A) 1.10 mg
  (B) 1.008 mg
  (C) 0.184 mg
  (D) 1.673 mg

Chemistry
Lahore Board 2015
Inter Part-I
Group-II
Time: 3.10 hrs.
Essay Type
Marks = 83

Section-I

2. Write short answers to any EIGHT (8) questions: (16)

• What are isotopes? Why they have same chemical but different physical properties?
• Write down stoichiometric assumption.
• Define molecular formula of a compound. How is it related with its empirical formula?
• Define sublimation and partition law.
• Differentiate between adsorption chromatography and partition chromatography.
• Write down the values of atmospheric chromatography pressure in four different units.
• Write down any two application of plasma.
• Burning of candle is a spontaneous process. Justify it.
• Differentiate between endothermic and exothermic reaction.
• State the law of mass action.
• How the value of equilibrium constant helps to predict the direction of a reversible reaction?
• What are buffer solutions? How a basic buffer can be prepared.

3. Write short answers to any EIGHT (8) questions: (16)

• What is isomorphism? Give an example.
• Transition temperature is the term used for elements as well as compounds. Explain.
• The vapour pressure of diethyl ether is higher than that of water at same temperature. Give reason.
• What are dipole-dipole forces of attraction? Explain with an example.
• State the Heisenberg’s Uncertainty Principle and give its mathematical form.
• Write down two defects of Rutherford’s Atomic Model.
• Give electronic distribution of ³¹₁₅P and ⁶⁶₂₉
• How neutrons were discovered by Chadwick? Give the equation of nuclear reaction involved.
• How the percentage ionic character of a covalent bond is determined by dipole moment?
• Differentiate between atomic orbital and molecular orbital.
• How the type of bonding affects solubility of compounds?
• State the geometry of NH₃ molecule on the basis of VSEPR theory.

4. Write short answers to any SIX (6) questions: (12)

• One molal solution of urea in water is dilute as compared to one molar solution of urea but the number of particles of solute is same. Justify it.
• What is Molarity? Calculate the Molarity of solution containing 9 grams of glucose (C₆H₁₂O₆) in 250 cm³ of solution.
• Differentiate between hydration and hydrolysis.
• Give the chemistry of electrolysis of aqueous solution of sodium chloride.
• What is electrolysis? Give example.
• Calculate oxidation number of Mn in KMnO₄ and Na₂MnO₄.
• Define half life period. How is it used to determine the order of reaction?
• What is specific rate constant or velocity constant?
• Enzymes are specific in action. Justify.

SECTION-II

Note: Attempt any THREE questions.

Question#5

(a) What is H-Bonding? Discuss H-Bonding in biological compounds. (4)
(b) NH₃ gas can be prepared by heating together two solids NH₄Cℓ and Ca(OH)₂. IF a mixture containing 100 gm of each solid is heated then calculate the number of grams of NH₃ produced. (At mass of C = 12 g/mole, N = 14 gm/mole, H = 1 gm/mole, Ca = 40 gm/mole, Cℓ = 35.5 gm/mole, O = 16 gm/mole). (4)

Question#6

(a) Explain Dalton’s law of partial pressure and give its application in berating process . (4)
(b) Write down the properties of cathode rays. 4

Question#7

(a) Explain paramagnetic behavior of O₂ on the basis of MOT and prove MOT is superior to other theories. (4)
(b) What is molar heat of combustion? How it is measured by bomb calorimeter?

Question#5

(a) What are enzymes? Give examples in which they act as catalyst. Mention the characteristics of enzymes. (4)
(b) Ca(OH)₂ is a sparingly soluble compound. Its solubility product is 6.5 x 10^-6. Calculate the solubility of Ca(OH)₂. (Atomic mass: Ca = 40). (4)

Question#5

(a)Give graphical explanation for elevation of boiling point of a solution. (4)
(b)Describe the electrolysis of molten NaCℓ and aqueous solution of NaCℓ. (4)

SECTION-III (Practical Part)

Note: (i) Attempt any THREE questions.
(ii Write down standard solution, chemical equation with mole ratio,indicator with end point, procedure and supposed reading with calculation for Part C, D, and E. 1, 1, 1, 1, 1
(iii)Write down material required, diagram and procedure for Part A and B.

A. Prepare pure sample of NACℓ by common ion effect. (5)
B. Separate the mixture of Pb²⁺ and Cd²⁺ ions by chromatography. (5)
C. 6.3 g of sample of . XH₂O is dissolved per Dm³ of solution. Determine the value of “X” (number of water molecules) volumetrically. (5)
D.The given solution contains partially oxidized FeSO₄O dissolved per dm³. Find out the percentage purity of the sample. (5)
E. The given solution contains 30.0 grains a mixture of Na₂S₂O₃.5H₂O and Na₂S₄O₆ dissolved per dm³. Find out the percentage of each component volumetrically. (5)