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Chemistry · Class 12 Science

Ch 1Solutions — Class 12 Chemistry, concept-first.

Truly pure substances are rare in everyday life. Almost everything around us — the air we breathe, the water we drink, the alloys in our coins and jewellery — is a mixture of two or more pure substances, and how useful or how dangerous that mixture is often depends entirely on the proportion of each ingredient present.

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Key concepts

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Mass Percentage

Imagine you're making lemonade. You mix 50 grams of sugar into 200 grams of water. The total drink weighs 250 grams.

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Chapter contents

The NCERT structure, section by section. Open a section to see its questions, then read the concept-first solution.

Introduction

Truly pure substances are rare in everyday life. Almost everything around us — the air we breathe, the water we drink, the alloys in our coins and jewellery — is a mixture of two or more pure substanc…

1.1

Types of Solutions

A solution is a homogeneous mixture of two or more components. "Homogeneous" means the composition and every property of the mixture are uniform throughout — wherever you sample it, it looks and behav…

1.2

Expressing Concentration of Solutions

8 Q

The concentration of a solution tells us how much solute is dissolved in a given amount of solvent or solution.

+Worked Examplesi3 questions
  1. Example 1.1Calculate the mole fraction of ethylene glycol ($C_2H_6O_2$) in a solution containing 20% of $C_2H_6O_2$ by mass.Free
  2. Example 1.2Calculate the molarity of a solution containing 5 g of NaOH in 450 mL solution.Preview
  3. Example 1.3Calculate molality of 2.5 g of ethanoic acid ($CH_3COOH$) in 75 g of benzene.Preview
+Intext Questions 1.1-1.5i5 questions
  1. 1.1Calculate the mass percentage of benzene ($C_6H_6$) and carbon tetrachloride ($CCl_4$) if 22 g of benzene is dissolved in 122 g of carbon te…Free
  2. 1.2Calculate the mole fraction of benzene in solution containing 30% by mass in carbon tetrachloride.Free
  3. 1.3Calculate the molarity of each of the following solutions: (a) 30 g of $Co(NO_3)_2 \cdot 6H_2O$ in 4.3 L of solution (b) 30 mL of 0.5 M $H_2…Preview
  4. 1.4Calculate the mass of urea ($NH_2CONH_2$) required in making 2.5 kg of 0.25 molal aqueous solution.Preview
  5. 1.5Calculate (a) molality (b) molarity and (c) mole fraction of KI if the density of 20% (mass/mass) aqueous KI is 1.202 g mL$^{-1}$.Preview
1.3

Solubility

The solubility of a substance is the maximum quantity of it that can be dissolved in a fixed amount of a particular solvent at a stated temperature (and, for gases, a stated pressure).

1.3.1

Solubility of a Solid in a Liquid

Not every solid dissolves in every liquid. Common salt and sugar dissolve freely in water, yet naphthalene and anthracene barely dissolve in it at all.

1.3.2

Solubility of a Gas in a Liquid

3 Q

Many gases dissolve in liquids, though to very different extents. Oxygen dissolves in water only slightly — yet that small amount of dissolved oxygen is what supports all aquatic life.

+Worked Examplesi1 question
  1. Example 1.4If $N_2$ gas is bubbled through water at 293 K, how many millimoles of $N_2$ gas would dissolve in 1 litre of water? Assume that $N_2$ exert…Preview
+Intext Questions 1.6-1.7i2 questions
  1. 1.6$H_2S$, a toxic gas with rotten egg like smell, is used for the qualitative analysis. If the solubility of $H_2S$ in water at STP is 0.195 m…Free
  2. 1.7Henry's law constant for $CO_2$ in water is $1.67 \times 10^8$ Pa at 298 K. Calculate the quantity of $CO_2$ in 500 mL of soda water when pa…Preview
1.4

Vapour Pressure of Liquid Solutions

A liquid solution is one in which the solvent is a liquid. The solute that dissolves in it can be a gas, another liquid, or a solid — so liquid solutions cover a wide range of everyday mixtures.

1.4.1

Vapour Pressure of Liquid-Liquid Solutions

Consider a binary solution of two volatile liquids, labelled component 1 and component 2. When this solution is kept in a closed vessel, both liquids evaporate.

+Worked Examplesi1 question
  1. Example 1.5Vapour pressure of chloroform ($CHCl_3$) and dichloromethane ($CH_2Cl_2$) at 298 K are 200 mm Hg and 415 mm Hg respectively. (i) Calculate t…Preview
1.4.2

Raoult's Law as a Special Case of Henry's Law

Two laws met earlier turn out to be closely related. Placing them side by side reveals that one is simply a special case of the other.

1.4.3

Vapour Pressure of Solutions of Solids in Liquids

A large and important class of solutions is made of solids dissolved in liquids — sodium chloride, glucose, urea and cane sugar dissolved in water, or iodine and sulphur dissolved in carbon disulphide…

1.5

Ideal and Non-ideal Solutions

Once we know how each liquid contributes its vapour pressure through Raoult's law, we can use that law as a test for how a real liquid-liquid mixture behaves.

1.5.1

Ideal Solutions

A solution that obeys Raoult's law over the whole range of concentration — from pure component A right through to pure component B — is called an ideal solution.

1.5.2

Non-ideal Solutions

When a solution fails to obey Raoult's law over the entire range of concentration, it is called a non-ideal solution.

+Intext Questions 1.8i1 question
  1. 1.8The vapour pressure of pure liquids A and B are 450 and 700 mm Hg respectively, at 350 K. Find out the composition of the liquid mixture if…Preview
1.6

Colligative Properties and Determination of Molar Mass

When a non-volatile solute is dissolved in a volatile solvent, the vapour pressure of the solvent falls (as established in the study of vapour pressure of solid-in-liquid solutions).

1.6.1

Relative Lowering of Vapour Pressure

The vapour pressure of a solvent in a solution is always less than that of the pure solvent. Raoult found that this lowering depends only on the concentration of the solute particles and not on their…

+Worked Examplesi1 question
  1. Example 1.6The vapour pressure of pure benzene at a certain temperature is 0.850 bar. A non-volatile, non-electrolyte solid weighing 0.5 g when added t…Preview
1.6.2

Elevation of Boiling Point

A liquid boils at the temperature where its vapour pressure becomes equal to the surrounding atmospheric pressure.

+Worked Examplesi2 questions
  1. Example 1.718 g of glucose, $C_6H_{12}O_6$, is dissolved in 1 kg of water in a saucepan. At what temperature will water boil at 1.013 bar? $K_b$ for wa…Free
  2. Example 1.8The boiling point of benzene is 353.23 K. When 1.80 g of a non-volatile solute was dissolved in 90 g of benzene, the boiling point is raised…Preview
1.6.3

Depression of Freezing Point

At its freezing point, a substance has its solid and liquid phases in dynamic equilibrium. A useful way to state this: the freezing point is the temperature at which the vapour pressure of the substan…

+Worked Examplesi2 questions
  1. Example 1.945 g of ethylene glycol ($C_2H_6O_2$) is mixed with 600 g of water. Calculate (a) the freezing point depression and (b) the freezing point o…Free
  2. Example 1.101.00 g of a non-electrolyte solute dissolved in 50 g of benzene lowered the freezing point of benzene by 0.40 K. The freezing point depressi…Preview
1.6.4

Osmosis and Osmotic Pressure

Many everyday observations share a hidden common cause: raw mangoes shrivel when pickled in brine, wilted flowers revive in fresh water, and blood cells collapse in saline water.

+Worked Examplesi1 question
  1. Example 1.11200 cm$^3$ of an aqueous solution of a protein contains 1.26 g of the protein. The osmotic pressure of such a solution at 300 K is found to…Preview
1.6.5

Reverse Osmosis and Water Purification

In ordinary osmosis, solvent flows into a solution across a semipermeable membrane. This direction can be turned around.

+Intext Questions 1.9-1.12i4 questions
  1. 1.9Vapour pressure of pure water at 298 K is 23.8 mm Hg. 50 g of urea ($NH_2CONH_2$) is dissolved in 850 g of water. Calculate the vapour press…Free
  2. 1.10Boiling point of water at 750 mm Hg is 99.63$^\circ$C. How much sucrose is to be added to 500 g of water such that it boils at 100$^\circ$C.Free
  3. 1.11Calculate the mass of ascorbic acid (Vitamin C, $C_6H_8O_6$) to be dissolved in 75 g of acetic acid to lower its melting point by 1.5$^\circ…Preview
  4. 1.12Calculate the osmotic pressure in pascals exerted by a solution prepared by dissolving 1.0 g of polymer of molar mass 185,000 in 450 mL of w…Preview
1.7

Abnormal Molar Masses

All four colligative properties studied so far — relative lowering of vapour pressure, elevation of boiling point, depression of freezing point, and osmotic pressure — depend only on the number of sol…

+Worked Examplesi2 questions
  1. Example 1.122 g of benzoic acid ($C_6H_5COOH$) dissolved in 25 g of benzene shows a depression in freezing point equal to 1.62 K. Molal depression const…Free
  2. Example 1.130.6 mL of acetic acid ($CH_3COOH$), having density 1.06 g mL$^{-1}$, is dissolved in 1 litre of water. The depression in freezing point obse…Preview

Summary

- Solution: A homogeneous mixture of two or more substances. Solvent is the component in larger amount; solute in smaller.

Exercises

+Show 41 questions41 questions
  1. 1.1Define the term solution. How many types of solutions are formed? Write briefly about each type with an example.Free
  2. 1.2Give an example of a solid solution in which the solute is a gas.Free
  3. 1.3Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.Free
  4. 1.4Concentrated nitric acid used in laboratory work is 68% nitric acid by mass in aqueous solution. What should be the molarity of such a sampl…Preview
  5. 1.5A solution of glucose in water is labelled as 10% w/w, what would be the molality and mole fraction of each component in the solution? If th…Preview
  6. 1.6How many mL of 0.1 M HCl are required to react completely with 1 g mixture of $Na_2CO_3$ and $NaHCO_3$ containing equimolar amounts of both?Preview
  7. 1.7A solution is obtained by mixing 300 g of 25% solution and 400 g of 40% solution by mass. Calculate the mass percentage of the resulting sol…Preview
  8. 1.8An antifreeze solution is prepared from 222.6 g of ethylene glycol ($C_2H_6O_2$) and 200 g of water. Calculate the molality of the solution.…Preview
  9. 1.9A sample of drinking water was found to be severely contaminated with chloroform ($CHCl_3$) supposed to be a carcinogen. The level of contam…Preview
  10. 1.10What role does the molecular interaction play in a solution of alcohol and water?Preview
  11. 1.11Why do gases always tend to be less soluble in liquids as the temperature is raised?Preview
  12. 1.12State Henry's law and mention some important applications.Preview
  13. 1.13The partial pressure of ethane over a solution containing $6.56 \times 10^{-3}$ g of ethane is 1 bar. If the solution contains $5.00 \times…Preview
  14. 1.14What is meant by positive and negative deviations from Raoult's law and how is the sign of $\Delta_{mix}H$ related to positive and negative…Preview
  15. 1.15An aqueous solution of 2% non-volatile solute exerts a pressure of 1.004 bar at the normal boiling point of the solvent. What is the molar m…Preview
  16. 1.16Heptane and octane form an ideal solution. At 373 K, the vapour pressures of the two liquid components are 105.2 kPa and 46.8 kPa respective…Preview
  17. 1.17The vapour pressure of water is 12.3 kPa at 300 K. Calculate vapour pressure of 1 molal solution of a non-volatile solute in it.Preview
  18. 1.18Calculate the mass of a non-volatile solute (molar mass 40 g mol$^{-1}$) which should be dissolved in 114 g octane to reduce its vapour pres…Preview
  19. 1.19A solution containing 30 g of non-volatile solute exactly in 90 g of water has a vapour pressure of 2.8 kPa at 298 K. Further, 18 g of water…Preview
  20. 1.20A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing…Preview
  21. 1.21Two elements A and B form compounds having formula $AB_2$ and $AB_4$. When dissolved in 20 g of benzene ($C_6H_6$), 1 g of $AB_2$ lowers the…Preview
  22. 1.22At 300 K, 36 g of glucose present in a litre of its solution has an osmotic pressure of 4.98 bar. If the osmotic pressure of the solution is…Preview
  23. 1.23Suggest the most important type of intermolecular attractive interaction in the following pairs. (i) n-hexane and n-octane (ii) $I_2$ and $C…Preview
  24. 1.24Based on solute-solvent interactions, arrange the following in order of increasing solubility in n-octane and explain. Cyclohexane, KCl, $CH…Preview
  25. 1.25Amongst the following compounds, identify which are insoluble, partially soluble and highly soluble in water? (i) phenol (ii) toluene (iii)…Preview
  26. 1.26If the density of some lake water is 1.25 g mL$^{-1}$ and contains 92 g of $Na^+$ ions per kg of water, calculate the molarity of $Na^+$ ion…Preview
  27. 1.27If the solubility product of CuS is $6 \times 10^{-16}$, calculate the maximum molarity of CuS in aqueous solution.Preview
  28. 1.28Calculate the mass percentage of aspirin ($C_9H_8O_4$) in acetonitrile ($CH_3CN$) when 6.5 g of $C_9H_8O_4$ is dissolved in 450 g of $CH_3CN…Preview
  29. 1.29Nalorphene ($C_{19}H_{21}NO_3$), similar to morphine, is used to combat withdrawal symptoms in narcotic users. Dose of nalorphene generally…Preview
  30. 1.30Calculate the amount of benzoic acid ($C_6H_5COOH$) required for preparing 250 mL of 0.15 M solution in methanol.Preview
  31. 1.31The depression in freezing point of water observed for the same amount of acetic acid, trichloroacetic acid and trifluoroacetic acid increas…Preview
  32. 1.32Calculate the depression in the freezing point of water when 10 g of $CH_3CH_2CHClCOOH$ is added to 250 g of water. $K_a = 1.4 \times 10^{-3…Preview
  33. 1.3319.5 g of $CH_2FCOOH$ is dissolved in 500 g of water. The depression in the freezing point of water observed is 1.0$^\circ$C. Calculate the…Preview
  34. 1.34Vapour pressure of water at 293 K is 17.535 mm Hg. Calculate the vapour pressure of water at 293 K when 25 g of glucose is dissolved in 450…Preview
  35. 1.35Henry's law constant for the molality of methane in benzene at 298 K is $4.27 \times 10^5$ mm Hg. Calculate the solubility of methane in ben…Preview
  36. 1.36100 g of liquid A (molar mass 140 g mol$^{-1}$) was dissolved in 1000 g of liquid B (molar mass 180 g mol$^{-1}$). The vapour pressure of pu…Preview
  37. 1.37Vapour pressures of pure acetone and chloroform at 328 K are 741.8 mm Hg and 632.8 mm Hg respectively. Assuming that they form ideal solutio…Preview
  38. 1.38Benzene and toluene form ideal solution over the entire range of composition. The vapour pressure of pure benzene and toluene at 300 K are 5…Preview
  39. 1.39The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volu…Preview
  40. 1.40Determine the amount of $CaCl_2$ ($i = 2.47$) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27$^\circ$C.Preview
  41. 1.41Determine the osmotic pressure of a solution prepared by dissolving 25 mg of $K_2SO_4$ in 2 litre of water at 25$^\circ$C, assuming that it…Preview

Answers to Intext Questions

These are the final answers printed at the end of the NCERT chapter. The book gives answers for some intext questions only — every question below links to our complete worked solution.

Exemplar Problems

Higher-order thinking / exemplar-style practice problems.

+Show 62 questions62 questions
  1. Q1Which of the following units is useful in relating concentration of solution with its vapour pressure? (i) mole fraction (ii) parts per mill…Free
  2. Q2On dissolving sugar in water at room temperature solution feels cool to touch. Under which of the following cases dissolution of sugar will…Free
  3. Q3At equilibrium the rate of dissolution of a solid solute in a volatile liquid solvent is __________. (i) less than the rate of crystallisati…Free
  4. Q4A beaker contains a solution of substance 'A'. Precipitation of substance 'A' takes place when small amount of 'A' is added to the solution.…Preview
  5. Q5Maximum amount of a solid solute that can be dissolved in a specified amount of a given liquid solvent does not depend upon ____________. (i…Preview
  6. Q6Low concentration of oxygen in the blood and tissues of people living at high altitude is due to ____________. (i) low temperature (ii) low…Preview
  7. Q7Considering the formation, breaking and strength of hydrogen bond, predict which of the following mixtures will show a positive deviation fr…Preview
  8. Q8Colligative properties depend on ____________. (i) the nature of the solute particles dissolved in solution. (ii) the number of solute parti…Preview
  9. Q9Which of the following aqueous solutions should have the highest boiling point? (i) $1.0\ M\ NaOH$ (ii) $1.0\ M\ Na_2SO_4$ (iii) $1.0\ M\ NH…Preview
  10. Q10The unit of ebullioscopic constant is _______________. (i) $K\ kg\ mol^{-1}$ or $K\ (molality)^{-1}$ (ii) $mol\ kg\ K^{-1}$ or $K^{-1}(molal…Preview
  11. Q11In comparison to a 0.01 M solution of glucose, the depression in freezing point of a 0.01 M $MgCl_2$ solution is _____________. (i) the same…Preview
  12. Q12An unripe mango placed in a concentrated salt solution to prepare pickle, shrivels because _____________. (i) it gains water due to osmosis.…Preview
  13. Q13At a given temperature, osmotic pressure of a concentrated solution of a substance _____________. (i) is higher than that at a dilute soluti…Preview
  14. Q14Which of the following statements is false? (i) Two different solutions of sucrose of same molality prepared in different solvents will have…Preview
  15. Q15The values of Van't Hoff factors for KCl, NaCl and $K_2SO_4$, respectively, are _____________. (i) 2, 2 and 2 (ii) 2, 2 and 3 (iii) 1, 1 and…Preview
  16. Q16Which of the following statements is false? (i) Units of atmospheric pressure and osmotic pressure are the same. (ii) In reverse osmosis, so…Preview
  17. Q17Value of Henry's constant $K_H$ ____________. (i) increases with increase in temperature. (ii) decreases with increase in temperature. (iii)…Preview
  18. Q18The value of Henry's constant $K_H$ is _____________. (i) greater for gases with higher solubility. (ii) greater for gases with lower solubi…Preview
  19. Q19A rectangular vessel is divided into two compartments by a vertical semipermeable membrane placed at its centre. The left compartment, side…Preview
  20. Q20We have three aqueous solutions of NaCl labelled as 'A', 'B' and 'C' with concentrations 0.1M, 0.01M and 0.001M, respectively. The value of…Preview
  21. Q21On the basis of information given below mark the correct option. Information: (A) In bromoethane and chloroethane mixture intermolecular int…Preview
  22. Q22Two identical 500 mL beakers are taken. Beaker 'A' is filled with 400 mL of pure water, while beaker 'B' is filled with 400 mL of a 2 M sodi…Preview
  23. Q23If two liquids A and B form minimum boiling azeotrope at some specific composition then _______________. (i) A-B interactions are stronger t…Preview
  24. Q244L of 0.02 M aqueous solution of NaCl was diluted by adding one litre of water. The molality of the resultant solution is _____________. (i)…Preview
  25. Q25On the basis of information given below mark the correct option. Information: On adding acetone to methanol some of the hydrogen bonds betwe…Preview
  26. Q26$K_H$ value for Ar(g), $CO_2$(g), HCHO(g) and $CH_4$(g) are 40.39, 1.67, $1.83\times10^{-5}$ and 0.413 respectively. Arrange these gases in…Preview
  27. Q27[Note: two or more options may be correct] Which of the following factor(s) affect the solubility of a gaseous solute in the fixed volume of…Preview
  28. Q28[Note: two or more options may be correct] Intermolecular forces between two benzene molecules are nearly of same strength as those between…Preview
  29. Q29[Note: two or more options may be correct] Relative lowering of vapour pressure is a colligative property because _____________. (i) It depe…Preview
  30. Q30[Note: two or more options may be correct] Van't Hoff factor i is given by the expression _____________. (i) $i = \dfrac{\text{Normal molar…Preview
  31. Q31[Note: two or more options may be correct] Isotonic solutions must have the same _____________. (i) solute (ii) density (iii) elevation in b…Preview
  32. Q32[Note: two or more options may be correct] Which of the following binary mixtures will have same composition in liquid and vapour phase? (i)…Preview
  33. Q33[Note: two or more options may be correct] In isotonic solutions ________________. (i) solute and solvent both are same. (ii) osmotic pressu…Preview
  34. Q34For a binary liquid solution, the total vapour pressure p (plotted on the vertical axis, increasing upward) is shown against the composition…Preview
  35. Q35[Note: two or more options may be correct] Colligative properties are observed when _____________. (i) a non volatile solid is dissolved in…Preview
  36. Q36Components of a binary mixture of two liquids A and B were being separated by distillation. After some time separation of components stopped…Preview
  37. Q37Explain why on addition of 1 mol of NaCl to 1 litre of water, the boiling point of water increases, while addition of 1 mol of methyl alcoho…Preview
  38. Q38Explain the solubility rule 'like dissolves like' in terms of intermolecular forces that exist in solutions.Preview
  39. Q39Concentration terms such as mass percentage, ppm, mole fraction and molality are independent of temperature, however molarity is a function…Preview
  40. Q40What is the significance of Henry's Law constant $K_H$?Preview
  41. Q41Why are aquatic species more comfortable in cold water in comparison to warm water?Preview
  42. Q42(a) Explain the following phenomena with the help of Henry's law. (i) Painful condition known as bends. (ii) Feeling of weakness and discomf…Preview
  43. Q43Why is the vapour pressure of an aqueous solution of glucose lower than that of water?Preview
  44. Q44How does sprinkling of salt help in clearing the snow covered roads in hilly areas? Explain the phenomenon involved in the process.Preview
  45. Q45What is 'semi permeable membrane'?Preview
  46. Q46Give an example of a material used for making semipermeable membrane for carrying out reverse osmosis.Preview
  47. Q47Match the items given in Column I and Column II. Column I: (i) Saturated solution; (ii) Binary solution; (iii) Isotonic solution; (iv) Hypot…Preview
  48. Q48Match the items given in Column I with the type of solutions given in Column II. Column I: (i) Soda water; (ii) Sugar solution; (iii) German…Preview
  49. Q49Match the laws given in Column I with expressions given in Column II. Column I: (i) Raoult's law; (ii) Henry's law; (iii) Elevation of boili…Preview
  50. Q50Match the terms given in Column I with expressions given in Column II. Column I: (i) Mass percentage; (ii) Volume percentage; (iii) Mole fra…Preview
  51. Q51Assertion: Molarity of a solution in liquid state changes with temperature. Reason: The volume of a solution changes with change in temperat…Preview
  52. Q52Assertion: When methyl alcohol is added to water, boiling point of water increases. Reason: When a volatile solute is added to a volatile so…Preview
  53. Q53Assertion: When NaCl is added to water a depression in freezing point is observed. Reason: The lowering of vapour pressure of a solution cau…Preview
  54. Q54Assertion: When a solution is separated from the pure solvent by a semipermeable membrane, the solvent molecules pass through it from pure s…Preview
  55. Q55Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why? (i) w…Preview
  56. Q56Using Raoult's law explain how the total vapour pressure over the solution is related to mole fraction of components in the following soluti…Preview
  57. Q57Explain the terms ideal and non-ideal solutions in the light of forces of interactions operating between molecules in liquid solutions.Preview
  58. Q58Why is it not possible to obtain pure ethanol by fractional distillation? What general name is given to binary mixtures which show deviation…Preview
  59. Q59When kept in water, raisin swells in size. Name and explain the phenomenon involved with the help of a diagram. Give three applications of t…Preview
  60. Q60Discuss biological and industrial importance of osmosis.Preview
  61. Q61How can you remove the hard calcium carbonate layer of the egg without damaging its semipermeable membrane? Can this egg be inserted into a…Preview
  62. Q62Why is the mass determined by measuring a colligative property in case of some solutes abnormal? Discuss it with the help of Van't Hoff fact…Preview

Sample & Board Papers

Sample papers and previous-year board questions for this subject.

+Show 3 questions3 questions
  1. Q150 mL of an aqueous solution of glucose $C_6H_{12}O_6$ (Molar mass: 180 g/mol) contains $6.02 \times 10^{22}$ molecules. The concentration o…Preview
  2. Q2Why a mixture of Carbon disulphide and acetone shows positive deviation from Raoult's law ? What type of azeotrope is formed by this mixture…Preview
  3. Q3Calculate the freezing point of an aqueous solution containing 10.5 g of Magnesium bromide in 200 g of water, assuming complete dissociation…Preview