12th Chemistry Question Bank 2023 PDF

महाराष्ट्र शासन द.ु क्र ०२०२४४७६९३८ शालेय शिक्षण व क्रीडा विभाग Email- राज्य शैक्षणिक संशोधन व प्रशिक्षण परिषद,महाराष्ट्र [email protected] ७०८ सदाशिव पेठ, कुमठे कर मार्ग, पणु े ४११०३०. प्रश्नपेढी (Question Bank) 2023...

महाराष्ट्र शासन द.ु क्र ०२०२४४७६९३८ शालेय शिक्षण व क्रीडा विभाग Email- राज्य शैक्षणिक संशोधन व प्रशिक्षण परिषद,महाराष्ट्र [email protected] ७०८ सदाशिव पेठ, कुमठे कर मार्ग, पणु े ४११०३०. प्रश्नपेढी (Question Bank) 2023 इयत्ता:- बारावी माध्यम:- इंग्रजी विषय:- रसायनशास्त्र (Chemistry) सच ू ना- 1. सदर प्रश्नपेढी ही १००% अभ्यासक्रमावर तयार करण्यात आली आहे. 2.सदर प्रश्नपेढीतील प्रश्न हे अधिकच्या सरावासाठी असन ू प्रश्नसंचातील प्रश्न बोर्डाच्या प्रश्नपत्रिकेत येतीलच असे नाही, याची नोंद घ्यावी.  Subject -CHEMISTRY (55) INDEX Sr. No. Name of Chapter Page no. 1. Solid State 3 E 2. Solutions 6 3. Ionic Equilibria 9 N 4. Chemical Thermodynamics 12 5. Electrochemistry 16 U 6. Chemical Kinetics 19 7. Elements of Groups16,17 and 18 22 8. 9. ,P Transition and Inner transition elements Coordination compounds 25 28 TM 10. Halogen Derivatives 31 11. Alcohols,Phenols and Ethers 34 12. Aldehydes,Ketones and Carboxylic acids 37 13. Amines 40 ER 14. Biomolecules 43 15. Introduction to Polymer Chemistry 46 16. Green Chemistry and Nanochemistry 49 SC 2  Chapter-1 Solid State Marks 3 with option 5 Multiple choice questions (1 mark) E 1. Which of the following types of solids contain molecules as constituent particles? a. molecular solids b. Ionic solids c. metallic solids d. covalent network solids N 2. Which of the following crystal systems contain four Bravais lattices? a.cubic b.tetragonal c.orthorhombic d.monoclinic 3. The number of spheres surrounded by octahedral void is—-- U a. 3 b. 4 c.6 d.8 4. The amorphous solid among the following is 5. ,P a. copper sulphate b.magnesium A paired cation-anion vacancy is called…… c.tar d. diamond TM a. Schottky b. Frenkel c. impurity d. vacancy defect defect defect defect 6. The unit cell of a simple cubic system has atoms at the eight corners. Hence, number of atoms in an unit cell is a. 1 b. 2 c. 3 8 7. In crystal lattice formed by primitive unit cell, the space occupied by particles is a.32% b. 47.6% c.52.4% d. 68% ER 8. The coordination number of spheres in hcp lattice in three dimension is a.2 b.4 c.6 d.12 9. A compound is made up of two elements X and Y and crystallizes in bcc structure. atoms of X are present at the corners of the cube. Atoms of Y are present at the center of the cube. The formula of the compound is a. X2Y b. XY c. XY2 d. X2Y3 SC 10. Sodium crystallizes in bcc structure. If the edge length of unit cell is 4.3X10-8 cm, the radius of Na atom is a. 1.86×10-8cm b. 1.52×10-8cm c. 2.15×10-8cm d. 4.3×10-8cm 3  Very short answer questions (1 Mark) 1. Write the effect on density of a substance in the Frenkel defect? 2. Write an example of a diamagnetic substance. 3. Give one property common to both hcp and ccp crystal lattices. E 4. Write the relationship between the radius of the atom and edge length of the fcc unit cell. 5. Draw diagram of bcc unit cell. N 6. Find the number of tetrahedral voids formed if the number of atoms in a crystal is N/2. 7. Write the percentage of empty space in the bcc lattice. 8. If the total volume of a simple cubic unit cell is 6.817×10-23 cm3, what is the volume occupied by U particles in the unit cell? (Ans:3.57×10-23 cm3) 9. Calculate the number of octahedral voids formed in 0.5 mol of a compound forming hcp structure ,P (Ans:3.011x1023) 10.Write the number of atoms in the fcc unit cell. TM Short answer questions (Type- I) (2 Marks) 1. Explain the terms: a) Isomorphism b) Polymorphism with examples 2. Classify the following solids as molecular, ionic, covalent and metallic solids. Pb, MgF2, SO2 and quartz 3. Explain vacancy defect with diagram. ER 4. Calculate the number of unit cells in 0.3 g of a species having density of 8.5 g/cm3 and unit cell edge length 3.25×10-8 cm. (Ans:1.028×1021) 5. A compound crystallizes in bcc structure. What is the unit cell edge length if the diameter of its atom is 120 pm? (Ans:138.6 pm) SC 6. Distinguish between crystalline solids and amorphous solids. 7. When gold crystallizes,it forms fcc unit cells.The unit cell edge length is 408 pm.Calculate the density of gold.Molar mass of gold is 197 g/mol. (Ans: 19.27g/cm3 ) 8. Explain the terms: a) Substitutional impurity defect b) Interstitial impurity defect. 4  Short answer questions (Type- II) (3 Marks) 1. Calculate the packing efficiency for bcc lattice. 2. In case of hcp structure, how are spheres in the first, second and third layers arranged? 3. A substance crystallizes in fcc structure. The unit cell edge length is 367.8pm. Calculate the molar mass of the E substance if its density is 21.5 g/cm3. (Ans:161.1 g/mol) 4. The unit cell of Na is bcc and its density is 0.97 g/cm3. What is the radius of a sodium atom if the molar mass of N Na is 23 g/mol? (Ans:1.86×10-8 cm) 5. Write classification of non-stoichiometric point defects. Explain with a diagram the metal deficiency defect. 6. Explain with one example each, the diamagnetic, paramagnetic and ferromagnetic substances. U 7. Write the relationship between ‘a’ and ‘r’ for sc,bcc and fcc unit cells. 8. Define: a. Diamagnetic solids b. Paramagnetic solids c. Ferromagnetic solid ,P Long answer questions (4 marks) 1. What are non stoichiometric point defects? Explain with a diagram the formation of F-centers. TM 2. Write the classification of stoichiometric point defects. What is a substitutional impurity defect? Explain solid solutions of metals and vacancy through aliovalent cations. 3. Derive the relationship between density of substance, its molar mass and the unit cell edge length. Explain how you will calculate the number of particles, and number of unit cells in x g of metal. 4. Define Bravais lattices. Niobium forms bcc structure. The density of niobium is 8.55 g/cm3 and the edge length ER of the unit cell is 330.6 pm.How many atoms and unit cells are present in 0.5 g of niobium? (Ans: no.of atoms- 3.237x10 21 and no.of unit cell- 1.618x1021) 5. Define: a. Conductors b. Insulators c. Semiconductors d. Doping SC 5  Chapter-2 Solutions Marks 4 with option 6 Multiple choice questions (1 Mark) 1. Sugar dissolves in water because a. sugar is nonpolar b. water is polar c. it forms hydrogen bonding d. sugar and water are both polar E with water 2. The solubility of a gas in water a. decreases with increase in temperature b. increases with increase in temperature N c.decreases with decrease in temperature d. is not affected by temperature 3. The units of Henry’s law constant are a. bar dm3 mol-1 b. mol L-1 bar-1 c. L mol -1 bar-1 d. bar L-1 mol-1 U 4. The colligative properties of solutions a. depend on nature of solute particles b. do not depend on number of solute particles 5. ,P c. do not depend on dissociation of solute in solvent d. depend on number of solute particles Which of the following solutions /solvent has maximum vapor pressure ? TM a. 1M copper sulphate solution b. pure solvent water c. 0.5M copper sulphate solution d.2M copper sulphate solution 6. According to Raoult’s law, relative lowering of vapor pressure of solution containing dissolved non-volatile solute a. is equal to mole fraction of solvent b. is equal to mole fraction of solute c. does not depend on mole fraction of solute d. is equal to molality of solution ER 7. Freezing point depression constant of a solvent is a. inversely proportional to molality of solution b. directly proportional to molarity of solution c. directly proportional to molality of solution d. expressed in K kg mol-1 8. Which of the following statements is applicable for 0.1M urea solution and 0.1M sucrose solution? SC a. osmotic pressure of urea solution is greater than that of sucrose solution b. osmotic pressure of sucrose solution is greater than that of the urea solution c. sucrose solution is not isotonic with urea solution d. both the solutions have the same osmotic pressure 9. The Henry’s law constant of a gas is 6.7×10-4 mol/(L bar). Its solubility when the partial pressure of the gas at 298 K is 0.65 bar is.. a.4.355×10-4 mol/L b. 4.355×10-2 mol/L c. 2.225×10-6 mol/L d. 2.225×10-2 mol/L 6  Very short answer questions (1 Mark) 1. What are hypertonic solutions? 2. What is cryoscopic constant? 3. Write the effect of dissolution of a nonvolatile solute on the freezing point of solvent. 4. Write the expression for relative lowering of vapor pressure. 5. State Raoult’s law. E 6. State Henry's law. 7. What type of solutions exhibit positive deviations from Raoult’s law? N 8. What is the enthalpy change and volume change on mixing of two components forming an ideal solution? 9. The vapor pressures of pure liquids A and B are 0.600 bar and 0.933 bar respectively, at a certain temperature. What is the mole fraction of solute when the total vapor pressure of their mixture is 0.8 bar? U (Ans:0.6004) 10. The vapor pressure of a pure liquid is 0.043 bar at a certain temperature. When a nonvolatile solute is dissolved ,P into it, the vapor pressure of the solution is found to be 0.041 bar. What is the relative lowering of vapor pressure? (Ans:0.0465) Short answer questions (Type- I) (2 Marks) TM 1. For a very dilute solution, the osmotic pressure is given by π = 𝑛2𝑅𝑇/𝑉 where V is the volume in L containing n2 moles of nonvolatile solute. Establish the equation for molar mass of solute. 2. Distinguish between ideal and non-ideal solutions. 3. Write two points to explain why vapor pressure of solvent is lowered by dissolving nonvolatile solute into it. ER 4. In what way Kf and Kb are similar and in what way they are different? 5. Calculate total moles after dissociation in 0.1M KCl solution and 0.05M aluminum sulphate solution.Which of the two solutions will have higher freezing point depression. (Ans: KCl=0.2mol, Al 2(SO4)3= 0.25 mol. Aluminium sulfate solution has higher freezing point SC depression) 6. When 50 g of a nonvolatile solute is dissolved in a certain quantity of solvent, the elevation of boiling point is 2.0 K. What will be the elevation of boiling point when 30 g of solute is dissolved in the same amount of the same solvent? (Ans:1.2 K) 7. The Henry's law constant of methyl bromide ( CH3Br),is 0.159 mol L-1 bar -1 at 250C.What is the solubility of methyl bromide in water at 250C and at pressure of 130 mmHg? (Ans: 0.02755M) 8. Explain the relationship between van’t Hoff factor and degree of dissociation. 7  Short answer questions (Type- II) (3 Marks) 1. Derive the expression for molar mass of solute in terms of boiling point elevation of solvent. 2. Explain the phenomenon of osmosis with a suitable diagram. 3. Explain with the help of vapor pressure-temperature curves for solution and solvent, why boiling point of solvent is elevated when a nonvolatile solute is dissolved into it. 4. A solution containing 3 g of solute A (M=60 g/mol) in 1L solution is isotonic with a solution containing 8.55 g E of solute B in 500 mL solution. What is the molar mass of B? (Ans:342 g/mol) 5. The vapor pressure of a pure solvent(water) at a certain temperature is 0.0227 bar. What is the vapor pressure of N a solution containing 6 g of solute (M=60 g/mol) in 50 g of solvent? (Ans:0.02188 bar) 6. Explain the relationship between van’t Hoff factor and degree of dissociation. U Long answer questions (4 Marks) ,P 1. What are non-ideal solutions? Explain with reasons and diagrams the positive and negative deviations from Raoult’s law shown by non-ideal solutions. 2. Explain with vapor pressure-temperature curves that the freezing point of a solvent is lowered by dissolving a TM nonvolatile solute into it. Give a reason for such lowering of freezing of solvent. 3. Definefollowing terms a) Reverse Osmosis b) Semi permeable membrane c) Osmotic pressure d) Isotonic solution. ER SC 8  Chapter-03 Ionic Equilibria Marks 4 - with option 06 Multiple choice questions (1 Mark) i) What is the percentage dissociation of 0.1 M Solution of acetic acid? E [ka(CH3COOH) = 10 -5] a) 0.01% b) 1% C) 10% d) 100% N ii) For a reaction HCl(aq)+ H2O (1) H3O+(aq) + C1 (-) (aq) Which of the following is a conjugate acid-base pair? a) H2O and Cl- b) H3O (+) and Cl- U c) H3O (+) and H2O d) HCl and H3O (+) iii) In biochemical system, pH of blood in our body is maintained due to following buffer ,P a) NH4OH + NH4Cl c) CH3 COOH + CH3COONa b) HCO3- + H2CO3 d) citric acid + Mg(OH)2 iv) If ‘IP’ is the ionic product and ‘k sp’ is the solubility product, precipitation of TM the compound will occur under the condition when. a) IP = k sp b) IP > k sp c) IP < k sp d) IP