BAHAWALPUR BOARD
Chemistry (New Scheme)
(Inter Part-I Class 11th)
Time: 20 minutes
Session (2019)
Objective
Marks: 17
Note: You have choices 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 with a marker or pen. Cutting or filling two or more circles will result in zero marks in that question.
Q.1: Answer all the following Multiple Choice Questions.
- Unit of rate constant is the same as that of the rate of reaction in:
A) First Order Reaction B) Second Order Reaction C) Zero Order Reaction D) Third Order Reaction - The stronger the oxidizing agent, the greater is the:
A) Oxidation Potential B) Reduction Potential C) Redox Potential D) E.M.F of Cell - The molal boiling point constant is the ratio of the elevation in boiling point to:
A) Molarity B) Molality C) Mole Fraction of Solvent D) Mole Fraction of Solute - Molarity of pure water is:
A) 1 B) 18 C) 55.5 D) 6 - The solubility product of AgCl is 2.0×10^-10 mol/dm³. The maximum concentration of Ag⁺ ions in the solution is:
A) 2.0×10^-10 mol/dm³ B) 1.41×10^-5 mol/dm³ C) 1.0×10^-10 mol/dm³ D) 40×10^-20 mol/dm³ - The change in heat energy of a chemical reaction at constant temperature and pressure is called:
A) Enthalpy Change B) Bond Energy C) Heat of Sublimation D) Internal Energy Change - Which of the following species has unpaired electrons in antibonding molecular orbitals:
A) O₂⁺ B) N₂ C) Br₂ D) I₂ - Which of the following molecules has zero dipole moment:
A) NH₃ B) CHCl₃ C) BF₃ D) H₂O - When the 6d orbital is complete, the entering electron goes into:
A) 7f B) 7s C) 7p D) 7d - Quantum number values for 2p orbitals are:
A) n = 2, l = 1 B) n = 1, l = 2 C) n = 1, l = 0 D) n = 2, l = 0 - Which of the following is a pseudo solid:
A) CaF₂ B) Glass C) NaCl D) All of these - Acetone and chloroform are soluble in each other due to:
A) Intermolecular Hydrogen Bonding B) Instantaneous Dipole C) Ion-Dipole Interaction D) All of these - The deviation of a gas from ideal behavior is maximum at:
A) -10°C, 5 atm B) -10°C, 2 atm C) 100°C, 2 atm D) 0°C, 2 atm - 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 - Solvent extraction is an equilibrium process and is controlled by:
A) Law of Mass Action B) The amount of solvent used C) Distribution Law D) The amount of solute used - The volume occupied by 1.4g of N₂ at STP is:
A) 2.24 dm³ B) 22.4 dm³ C) 1.12 dm³ D) 112 cm³ - 27g of Al will react completely with how much mass of O₂ to produce Al₂O₃:
A) 8 g Oxygen B) 16 g Oxygen C) 32 g Oxygen D) 24 g Oxygen
BAHAWALPUR BOARD
Chemistry (New Scheme)
Session (2019)
(Inter Part-I Class 11th)
Subjective
Time: 2 hours 40 minutes
Marks: 68
Note: Section I is compulsory. Attempt any three (3) questions from Section II.
Section I
Q.2: Write short answers to any eight (8) of the following parts.
(8×2 = 16)
i. Define Relative Atomic Mass. Also, give two examples.
ii. How can the efficiency of a reaction be expressed? Write down its formula.
iii. Differentiate between Molecule and Molecular ion.
iv. Describe the features of an ideal solvent.
v. Prove that d=PM/RT
vi. Calculate the value of the gas constant (R) in SI units.
vii. Define Plasma. Also, give its one application.
viii. Write down the S.I units of ‘a’ and ‘b’ in van der Waal’s equation.
ix. Differentiate between ideal and non-ideal solutions.
x. One Molal solution of Urea in water is dilute compared to one Molar solution of Urea, but the number of solute particles is the same. Justify this statement.
xi. Define Mole Fraction. Also, write down its formula.
Q.3: Write short answers to any eight (8) of the following parts.
i. Evaporation causes cooling. Justify.
ii. Boiling needs a constant supply of heat. Justify.
iii. How do earthenware vessels keep water cool?
iv. Vacuum distillation can be used to avoid the decomposition of a sensitive liquid. Justify.
v. Why is it necessary to decrease the pressure in the discharge tube to get cathode rays?
vi. Why are positive rays also called canal rays?
vii. Regardless of the gas used in the discharge tube, the nature of cathode rays remains the same. Why?
viii. Differentiate between slow-moving neutrons and fast-moving neutrons.
ix. Why does the solubility of glucose in water increase with increasing temperature?
x. Define pH and pOH.
xi. Give two properties of enzymes.
xii. Differentiate between the average and instantaneous rate of reaction.
Q.4: Write short answers to any six (6) of the following parts.
i. Define a Polar Bond. Give the formulas of two diatomic molecules that have polar bonds.
ii. Define Coordinate Covalent Bond. Draw the Coordinate Covalent Bond between NH₃ and BF₃ molecules.
iii. Why is Molecular Orbital Theory superior to Valence Bond Theory?
iv. The dipole moment of CO₂ is zero, but that of SO₂ is greater than zero. Justify.
v. Define System and Surrounding with reference to Thermochemistry.
vi. Define Enthalpy of Neutralization. Write the thermochemical equation for the enthalpy of neutralization between a strong acid and a strong base.
vii. Show that the oxidation number of Cr in K₂Cr₂O₇ is +6.
viii. Write the oxidation and reduction reactions at the anode and cathode for the electrolysis of fused NaCl.
ix. The Standard Hydrogen Electrode (SHE) acts as the anode when connected to a copper electrode but acts as the cathode when connected to a zinc electrode. Explain briefly.
Section II
Note: Attempt any three (3) questions.
Q.5
a) Define Actual Yield. Why is the actual yield usually less than the theoretical yield? Write down the formula for Percentage Yield.
b) Give any four characteristics of Covalent Solids.
Q.6
a) One mole of methane gas is maintained at 300 K, and its volume is 250 cm³. Calculate the pressure exerted by the gas.
b) Derive the equation for the radius of the nth orbit of a hydrogen atom using Bohr’s model.
Q.7
a) Define Atomic Orbital Hybridization. Explain sp²-hybridization, giving the example of BF₃.
b) Differentiate between Spontaneous and Non-Spontaneous processes with examples.
Q.8
a) Calculate the pH of a buffer solution in which 0.11 M CH₃COONa and 0.09 M acetic acid solutions are present. The value of KaK_a for CH₃COOH is 1.85×10−51.85 \times 10^{-5}.
b) Write two factors that affect the rate of a reaction.
Q.9
a) Define Hydrolysis. Explain it with two examples.
b) Write any four applications of the Electrochemical Series.