Jr. INTER CHEMISTRY Important Questions

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1 Jr. INTER CHEMISTRY Important Questions 1. ATOMIC STRUCTURE (8 Marks) Long Answer type Questions 1. What are the postulates of Bohr's model of hydrogen atom? Give any two limitations of this model. Discuss the importance of this model to explain various series of line spectra in Hydrogen atom. 2. What are Quantum numbers? Explain the significance of quantum numbers. 2. CLASSIFICATION OF ELEMENTS AND PERIODICITY IN PROPERTIES (8 Marks) Long Answer type Questions 1. What are first and second Ionisation Enthalpy? Why I.E. 2 > I.E. 1 Explain four factors influencing Ionisation Enthalpy? 2. What is a periodic property? How the following properties vary in a group and in a period? a) Atomic radius b) I.E. c) E.N. d) Nature of Oxides e) Electron gain enthalpy 3. Write an essay on s, p, d and f block elements. 3. CHEMICAL BONDING AND MOLECULAR STRUCTURE (8 Marks) Long Answer type Questions 1. What do you understand by hybridization? Explain the different types of hybridizations involving 's' and 'p' orbitals. 1. Give an account of VSEPR theory. 2. Explain sp 3 d hybridization with one example. 3. Explain sp 3 d 2 hybridization with one example. 4. Explain the formation of coordinate covalent bond with two examples. 5. What is "Hydrogen bond"? Explain the different types of Hydrogen bonds with suitable examples. 6. Explain molecular orbital theory of oxygen molecule (& N 2 molecule). Calculate its bond order and explain its magnetic property.

2 Very 1. What is "Octet rule"? 2. Which of the two ions Ca +2 or Zn +2 is more stable and why? 3. How many sigma and pi bonds are present in a) C 2 H 2 and b) C 2 H 4 4. If A and B are two different atoms when does AB molecule become covalent? 5. Boiling point of H 2 O is higher than HF. Why? 6. Why H 2 O has dipole moment while CO 2 does not have? 7. Even though N in NH 3 is in sp 3 hybridizaiton, the HNH bond angle deviate from '. Why? 8. Define dipole moment. 9. NH 3 has higher dipole moment compared to NF 3. Why? 10. Be - F bonds are polar, but dipole moment of BeF 2 is zero. Why? 4. STATES OF MATTER : GASES AND LIQUIDS (6 Marks) 1. Write any four postulates of the kinetic molecular theory of gases. 2. Derive "Charles law" and "Graham's law" of diffusion from kinetic gas equation. (Learn Boyle's Law and Dalton's Law also) 3. State and explain "Graham's law of diffusion". 360 cm 3 of CH 4 gas diffused through a porus membrane in 15 minutes. Under similar conditions, 120 cm 3 of another gas diffused in 10 minutes. Find the molar mass of the gas. 4. State and explain Dalton's Law of partial pressures. Very 1. Calculate kinetic energy of 5 moles of N 2 at 27 C. 2. What is "Boltzmann's constant?" Give its values. 3. Which of the gases diffuses faster among N 2, O 2 and CH 4. Why? 4. Give the ratio of RMS, average and most probable speeds of gas molecules. 5. What is "surface tension"? 6. What is "coefficient of viscosity"? Give its units. 7. Find the rms, average and most probable speeds of O 2 at 27 C.

3 5. STOICHIOMETRY (6 Marks) 1. Balance the following redox equation by ion - electron method taking place in acidic medium. Cr 2 O SO 2 3 Cr +3 + SO 2 4 Other reactions for practice: Cr 2 O NO 2 Cr +3 + NO 3 MnO 4 + SO3 2 Mn +2 + SO 2 4 SO Br SO 2 + Br 2 MnO C 2 O 2 4 Mn +2 + CO 2 MnO 4 + Br MnO2 + BrO 3 2. Balance the following redox equation by ion-electron method taking place in basic medium. Cr(OH) 3 + IO OH 3 I + CrO Chemical analysis of a carbon compund, gave the following percentage composition by weight of the elements present, Carbon = 10.06%, Hydrogen = 0.84%, Chlorine = 89.1%. Find the empirical formula of the compound. 4. A carbon compound contains 12.8% Carbon, 2.1% Hydrogen, 85.1% Bromine. The molecular weight of the compound is Find the molecular formula. Very 1. What volume of CO 2 is obtained at STP by heating 4 g of CaCO 3? 2. How many moles of glucose are present in 540 g of glucose? 3. The empirical formula of a compund is CH 2 O. Its molecular weight is 90. Find the molecular formula of the compound. 4. Calculate the molarity of NaOH in the solution perpared by dissolving 4 g in enough water to form 250 ml of the solution. 5. Calculate the normality of oxalic acid containing 6.3 g of H 2 C 2 O 4. 2 H 2 O in 500 ml of solution. 6. Calculate the volume of O 2 at STP required to completely burn 100 ml of acetylene. 7. What is disproportionation reaction? Give one example. 8. Assign oxidation number of the underlined elements of the following species. a) H 4 P 2 O 7 b) K 2 Mn O 4

4 6. THERMODYNAMICS (4 Marks) 1. State and explain Hess's law of constant heat summation. Explain with one example. 2. State the first law of thermodynamics. Explain its mathematical notation. 3. Explain the terms a) Entropy b) Heat Capacity c) Enthalpy of formation and d) Enthalpy of combustion. 4. Calculate the standard enthalpy of formation of CH 3 OH (l) from the following data. CH 3 OH (l) + 3 O 2 2 (g) CO 2 (g) + 2 H 2 O (l); r H ( ) = 726 K.J. mol 1 C (graphite) + O 2 (g) CO 2 (g); r H (-) = 393 K.J.mol 1 H 2 (g) O 2 (g) H 2 O (l); f H (-) = 286 K.J. mol 1. Very 1. The equilibrium constant for a reaction is 10. What will be the value of G (-)? (R = J.K. 1 mol 1, T = 300 K) 2. Given N 2 (g) + 3 H 2 (g) 2 NH 3 (g); H = K.J. mol 1. What is the standard enthalpy of formation of NH gas? 3 3. State 2nd & 3rd laws of thermodynamics. 4. What are "extensive and intensive properties?" 5. Give the equation that gives the relationship between U and H. 7. CHEMICAL EQUILIBRIUM AND ACIDS - BASES (6 Marks) 1. Derive the relationship between k p and k c for the equilibrium reactions. a) 2 SO 2 (g) + O 2 (g) 2 SO 3 (g) and b) N 2 (g) + 3 H 2 (g) 2 NH 3 (g) 2. State Le Chatlier's principle. Discuss the principle for the industrial synthesis of NH 3 (or SO 3 ). 3. Explain Lewis Acid - Base theory with suitable examples. 4. Explain the concept of Bronsted acids and Bronsted bases. 5. What is "Salt Hydrolysis"? Aqueous solution of NH 4 Cl is acidic where as aqueous solution of CH 3 COONa is basic. Why? Explain. 6. Explain the following. a) Common ion effect b) Solubility product 7. What are Buffer solutions? Classify with one example each.

5 Very 1. Calculate ph of 0.05 M NaOH solution. 2. Concentration of Hydrogen ion is M. What is its ph? 3. What is homogeneous equilibrium? Give two examples. 4. What is heterogeneous equilibrium? Give 2 examples. 5. What is the value of k w at room temperature? What are its units? 6. Define ph. Calculate the ph of 0.05 M Ba(OH) 2 aqueous solution ml of 1 M CH 3 COOH solution, when added to 50 ml of 0.5 M NaOH gives a solution with ph value 'x'. Find the value of 'x'. (p ka of acetic acid is 4.8) 8. The solubility of Ag 2 CrO 4 is mol L 1. What is the solubility product? 9. What is the ph of 10 8 M HCl? 10. k c for the reaction, N 2 (g) + 3 H 2 (g) 2 NH 3 (g) is 0.5 at 400 K. Find k p. 8. HYDROGEN AND ITS COMPOUNDS (4 Marks) 1. What is hardness of water? Write i) ion - exchange method ii) Calgon's method for the removal of permanent hardness of water. 2. Write few lines on the utility of Hydrogen as a fuel. 3. Write the chemical reactions to justify that hydrogen peroxide can function as oxidising as well as reducing agent. 4. Discuss with relevant chemical equations, various methods of preparing hydrogen peroxide. 5. Explain the terms a) SYNGAS b) Coal gasification C) autoprotolysis and d) interstitial hydride. 9. THE s - BLOCK ELEMENTS (4 Marks) Very 1. Why are alkali metals not found in a free state in nature? 2. Give the reactions involved in Castner - Kellner process? 3. Write about biological importance of Ca & Mg. 4. Write about biological importance of Na + & K + ions. 5. Write any two uses of Caustic soda. 6. Why does the solubility of alkaline earth metal hydroxides in water increase down the group? 7. Why is gypsum added to cement? 8. Write any two uses of Sodium Carbonate. 9. Give two uses of Plaster of Paris. 10. Write the average composition of Portland cement.

6 10. THE p - BLOCK ELEMENTS GROUP - 13 (4 Marks) 1. What is Borax? Explain the borax bead test with a suitable example. 2. Explain the structure of Diborane. 3. How does diborane react with a) H 2 O b) CO c) N(CH 3 ) 3 d) NH 3, Very 1. What is inert pair effect? Why TlCl 3 has higher stabilility? 2. What is the hybridisation of B in a) diborane and b) borazine? 3. Give the formula and strcuture of borazine. What is its common name? 4. Sketch the structure of orthoboric acid. 5. Can Conc. HNO 3 be transported in aluminium container? Why? GROUP - 14 (4 Marks) 1. Explain the difference in properties of diamond and graphite on the basis of their structure? 2. Write a short note on a) Silicates and b) Zeolites. Very 1. Why is Carbon monoxide poisonous? 2. What is allotropy? Give the crystalline allotropes of Carbon and mention the hybridisation present in them. 3. Why Diamond is hard? 4. Graphite is a good conductor - explain. 5. How does graphite function as a lubricant? 6. SiO 2 is solid while CO 2 is a gas - explain. 7. Write the use of ZSM SiF 2 6 is known while SiCl 2 6 is not - explain. 9. CO 2 is useful as well as harmful - explain. 10. Diamond has high melting point - explain. 11. What is 'synthesis gas'? How is it prepared? 12. What is 'producer gas'? How is it prepared?

7 12. ENVIRONMENTAL CHEMISTRY (4 Marks) 1. Define 'receptor' and 'sink'. 2. Define 'BOD' and 'COD'. 3. Define 'pollutant' and 'contaminant'. 4. Define 'TLV' and 'Eutrophication'. 5. Which oxides cause acid rain? What is its ph value? 6. What are the effects of acid rains? 7. What is Ozone hole? Where was it first observed? 8. What is 'Green house effect'? and how is it caused? 9. Give the possible BOD values of clean water and the polluted water. 10. What is the dissolved Oxygen in pure cooled water? 13. ORGANIC CHEMISTRY - SOME BASIC PRINCIPLES AND TECHNIQUES (10 Marks) 1. Write about position isomerism and functional group isomerism. 2. Discuss Markownikov's rule and Kharash effect. 3. Write the possible conformations of ethane and explain which is more stable? 4. Explain "Wurtz reaction" and "Friedel Crafts Alkylation" with one example. 5. Describe two methods of preparation of ethylene. Give the equations. 6. Give equations for the reactions of ethylene with the following. a) Ozone b) Hypohalous acid c) Cold & Dil. KMnO 4 and d) Heated with O 2 at high pressure. 7. Describe two methods of preparation of acetylene. Give the equations. 8. Give equation for the reactions of acetylene with the following. a) Water b) Ozone C) Hydrogen halide and d) Ammonical AgNO 3 and Cu 2 Cl Describe two methods of prepration of Benzene. Give the equations. 10. Give equation for the reactions of benzene with a) Conc. HNO 3 + Conc. H 2 SO 4 b) CH 3 Cl + Anhyd. AlCl 3 c) CH 3 COCl + Anhyd. AlCl 3 and d) Cl 2 + Anhyd. AlCl Explain the following. a) Inductive effect b) Mesomeric effect c) Resonance effect and d) Hyper conjugation. 12. Complete the following reaction and name the products A, B and C. H 2 O hot metal tube AlCl 3 + CH 3 Cl CaC 2 A B C

8 13. Name the products A, B and C formed in the following reactions. Give the equations for the reactions. Br 2 / CCl 4 Alc. KOH Br 2 Ethylene A B C Very 1. Write the structural formulae of the following compounds: a) Trichloroethanoic acid b) Neo - pentane 2. Write IUPAC names of the following: CH 3 a)h 3 C C CH CH 2 CH 3 CH 3 CH 3 CH 3 b) H 3 C C CH 2 COOH CH 3 3. Write IUPAC names of the following: O a) b) O 4. Discuss Lassaigne's test. 5. Explain the principle of Chromatography. 6. What are a) Electrophiles and b) Nucleophiles. 7. Write structures and IUPAC names of any two different structural isomers of alkenes corresponding to C 5 H Draw cis and trans isomers of the compound CHCl = CHCl. 9. Write the E and Z configuration of an alkene contains on carbons at double bond Cl, Br and CH 2 CH 2 OH, CH(CH 3 ) What is geometrical isomerism? Write geometrical isomers of 2 - butene. (Note: Though there is no blue print, marks in the bracket were given according to latest exam papers). Prepared by A.N.S. Sankara Rao, Senior Lecturer.