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1st year Chemistry Guess paper
SECTION "A" - MCQs MULTIPLE CHOICE QUESTIONS
NOTE Attempt all questions from this section.
Q.1. Choose the correct answer for each from the given options.
i. The significant figures in the number 5.734 are
SECTION "B" - SHORT ANSWER QUESTIONS
Q.2. Answer any TEN questions from this section. All questions carry equal marks. The answer to each question should not exceed 6-8 lines.
1. Define the following terms
2. Give the main posulates of the Kinetic Molecular Theory of Gases.
State the following Gas Laws
3. Write two points of difference between each of the following
4. Calculate the value of the gas constant R when "p" is expressed in atmospheres and "V" in dm3 and when MKS system is used.
Derive the equation for the radius of the nth orbit of hydrogen atom using Bohr's Postulates.
5. Draw the shapes of s-orbital and p-orbital. Write down the names of the spectral lines of hydrogen atom.
Write down the values of all the four quantum number for each of the two electrons of helium atom.
6. Diethyl Zinc is a chemical used in laboratory to protect the books from the worms. Its composition is 53% Zinc, 38.9% Carbon and 8.1% Hydrogen, find the emperical formula of the compound.
Find the mass, number of moles and volume of Carbon Dioxide gas at S.T.P obtained on burning of 6.0g of carbon. Give also equation. Also find the number of molecules of CO2.
You are provided with 6.0gm of C and 100 gm of O2. Calculate the amount of CO2 prepared by reacting them. Which of them is a limting reactant.
Ethylene glycol is used in automobiles as antifreeze. It has 38.7% Carbon 9.7% Hydrogen and 51.6% Oxygen. Its molecular mass is 62.0 mol-1. Determine its molecular formula
7. Define Radioactivity. Describe the experiment to distinguish the three types of radioactive radiation.
Write down five properties of each Alpha (α), Beta (β), Gamma (γ) rays.
What are Cathode Rays? How are they produced? Discuss the five properties of Cathode Rays.
8. What do you understand by the ionic character of a covalent bond.
Describe the ionic character of a covalent bond with one example.
Define coordinate covalent bond and explain the formation of (NH+4).
9. Give a brief account of the following
10. Write down the postulates of Arrhenius Theory of Ionization.
Define the terms Oxidation and Reduction. Which of the substances is a reducing agent in the reaction Zn + H2SO4 ------> ZnSO4 + H2.
11. State the First Law of Thermodynamics. Derive the equation.
State and explain Hass's Law of constant heat summation.
12. In a certain process 848J of heat is absorbed by s system, while 394J of work is done on the system. What is the change in internal energy of the process.
Write down the electronic configuration for the ground state in Na (Z = 11) and Mg+2 (Z = 12).
Give the number of protons, neutrons and electrons in 19/39K and 9/19F.
13. Arrange the following energy levels in ascending order using (n + 1) rule 4d, 3p, 7s, 4f, 2s.
Calculate the wave number of radiation emitted in Lyman series of hydrogen atom when electron jumps from 2nd to Ist orbit.
14. For the reaction 2Hl(g) <-------> H2(g) + 12(g), one mole of Hl is introduced into a vessel at constant temperature, calculate the number of moles of I2 when the equilibrium reached (Kc = 0.0156).
Will PbCrO4 precipitate from a solution prepared by mixing 200 cm3 of 2.5 x 10-4 M Pb(NO3)2 and 600 cm3 of 1.5 x 10-8 M K2Cro4? (Ksp of PbCrO4 = 1.8 x 10-14 mol-2 dm-6)
15. Give scientific reasons for the following
SECTION "C" - DETAILED ANSWER QUESTIONS
NOTE Attempt any TWO questions from this Section. All questions carry equal marks:
Q.3 (A). Differentiate between the following
What is Dipole Moment? Explain the shapes of CO2 and H2O molecules with the help of dipole moment.
Q.3 (C). Describe the following rules of electronic configuration.
Differentiate between the following
Q.4 (A). State the Law of Mass Action. Derive the equilibrium constant Kc for the reaction nA + nB <--------> xC + yD.
State Rutheford's Nuclear Model of an atom on the basis of Rutherford's Experiment.
What are the defects of Rutherford's Atomic Model? How Neil Bohr corrected them. Describe the postulates of Bohr's Atomic Theory.
State and explain Le-Chatelier's Principle.
Q.4 (B). What are ionization Potential and Electron Affinity. Discuss the formation of bond between Sodium and Chlorine.
Define Solubility Product and give its example and application.
What is Electrode Potential? How is electrode potential and Zinc and Copper discovered.
Define rate of reaction describe methods to determine the rate of reaction and also describe the factors which affect the rate of reaction.
Q.4 (C). Calculate the rate constant for the reaction A + B --------> AB when the initial concentration of each of the reactant is 0.01 mol-1 dm-3 S-1.
The volume of a given mass of a gas at 127°C is 2.0 dm3. What will be its volume at 254°C when pressure remains constant.
Q.5 (A). Differentiate between the following
Define the following terms
Q.5 (B) ii. Balance the following equation by Ion Electron method.
Fe(+3) + MnO4(-1) ----------> Fe+3 + Mn(+2) + H2O
Q.3 (C). Name the crystal system which has the following axis and angle.