KEAM Solutions — practice questions
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Practice KEAM Solutions in the app →Which statement correctly describes Raoult's law for an ideal solution of two volatile liquids A and B?Colligative properties of a dilute solution depend on:
The figure shows a non-ideal solution with *The molal boiling-point elevation constant of water is $K_b = 0.52$ K kg/mol. What is the boiling point of a s$36$ g of glucose ($M = 180$ g/mol) is dissolved in $200$ g of water. The molality of the solution is:The van't Hoff factor $i$ for a $0.01$ M aqueous solution of NaCl, assuming complete dissociation, is approximA solution is best defined as:In a salt-in-water solution, the solvent is:The empirical rule 'like dissolves like' predicts that:Henry's law states that the solubility of a gas in a liquid is:Which of the following is **not** a colligative property?When a non-volatile solute is dissolved in a volatile solvent, the vapour pressure of the solution:The boiling point elevation $\Delta T_b$ of a dilute solution is:For an **ideal** solution, the enthalpy of mixing $\Delta_{mix}H$ is:Raoult's law for a volatile component of a solution states $P_i$ equals:With increase in temperature, the solubility of most gases in water:The solubility of N₂ gas in water at 25 °C and 1 bar is $6.85 \times 10^{-4}$ mol L⁻¹. If the partial pressureIf 18 g of glucose (M = 180 g/mol) is dissolved in 90 g of water (M = 18 g/mol), the mole fraction of glucose Which of the following statements about ideal and non-ideal solutions is **incorrect**?The graph in the figure shows a solution whose total vapour pressure is **higher** than that predicted by RaouThe pV-curve shown represents a solution exhibiting **negative** deviation from Raoult's law. Which mixture isThe figure shows the variation of solubility of common ionic solids in water with temperature. According to thWhich gas does **not** obey Henry's law in water, because it reacts chemically with the solvent?Which of these statements about the effect of pressure on solubility is correct?The relative lowering of vapour pressure of a dilute solution of a non-volatile solute equals:If $K_b$ for water is 0.512 K·kg/mol, the boiling point elevation of a 0.50 molal aqueous urea solution is:For an ideal solution of two volatile liquids, the relationship between solvent–solvent, solute–solute and solA binary solution of two volatile liquids A (P°₁ = 450 mm Hg) and B (P°₂ = 700 mm Hg) at 350 K has a total vapFor the same binary solution (P°₁ = 450 mm Hg, P°₂ = 700 mm Hg, total P = 600 mm Hg, $x_1 = 0.4$, $x_2 = 0.6$)A solution of 394 g of a non-volatile solute in 622 g of water has vapour pressure 30.74 mm Hg at 30 °C. The vThe Henry's law constant of CH₃Br in water at 25 °C is 0.159 mol L⁻¹ bar⁻¹. The solubility of CH₃Br at 25 °C a2.315 g of a non-volatile solute is dissolved in 49 g of benzene (M = 78 g/mol). The vapour pressure of pure bA solution that shows **positive** deviation from Raoult's law typically has:If the vapour pressure of water at a particular temperature is 25 mm Hg, and 1 mol of a non-volatile solute isEqual masses of glucose (M = 180), urea (M = 60) and sucrose (M = 342) are dissolved in equal masses of water,Two liquids A and B form an ideal solution. At a certain temperature, the vapour pressure of pure A is 100 mm Solutions are homogeneous mixtures of two or more components. In a binary solution, the component present in tAn amalgam of mercury with sodium is an example of which type of solution?Which of the following concentration units is *temperature-dependent*?The sum of mole fractions of all components in a solution equals:Molality (m) is defined as:Calculate the molality of a solution prepared by dissolving 2.5 g of ethanoic acid (CH₃COOH, M = 60 g mol⁻¹) iThe molarity of a solution containing 5 g of NaOH (M = 40 g mol⁻¹) in 450 mL of solution is:The mole fraction of ethylene glycol (C₂H₆O₂, M = 62) in a 20% by mass aqueous solution is approximately:If sea water (density 1.03 g mL⁻¹) contains 5.8 g of dissolved O₂ per 10⁶ g of water, the concentration is bes'Like dissolves like' implies that:If dissolution of a solid in a liquid is endothermic (Δ_sol H > 0), the solubility will:Solubility of gases in liquids generally:Henry's law states that, at a constant temperature, the partial pressure (p) of a gas above a solution is:The Henry's law constant (K_H) values for N₂ at 293 K and 303 K are 76.48 and 88.84 kbar respectively. This shScuba divers ascending from depth too quickly may suffer from the 'bends', caused by:To increase the solubility of CO₂ in soft drinks, manufacturers:Anoxia, observed in high-altitude climbers, is best explained by:Raoult's law for a solution of two volatile liquids states that the partial pressure of component 1 is:For a binary solution of volatile liquids, the total vapour pressure can be written as:At equilibrium, the vapour phase above a liquid solution is always richer in the component that:Raoult's law in its general form, for the solvent in a solution of a non-volatile solute, gives the relative lFor an ideal solution, both the enthalpy of mixing and the volume of mixing are:Which of the following is an example of a near-ideal solution?A solution shows **positive deviation** from Raoult's law when:A solution of chloroform and acetone shows **negative deviation** from Raoult's law because:Solutions showing large **positive deviation** from Raoult's law form which type of azeotrope?Azeotropes are binary mixtures that:Ethanol–water mixture, on fractional distillation, gives an azeotrope at approximately:HNO₃–water mixture forms a *maximum* boiling azeotrope at composition:Which of the following is NOT a colligative property?The four colligative properties all originate from:Elevation of boiling point (ΔT_b) is related to molality (m) by:For water, K_b = 0.52 K kg mol⁻¹. What is the boiling point of a solution of 18 g glucose (M = 180) in 1 kg waDepression of freezing point (ΔT_f) is given by:45 g of ethylene glycol (M = 62) is dissolved in 600 g of water. K_f(water) = 1.86 K kg mol⁻¹. The depression Which property allows osmotic pressure to be especially useful for determining the molar mass of macromoleculeThe osmotic pressure (Π) of a dilute solution is given by:Two solutions are termed *isotonic* if they:Blood cells placed in a hypertonic solution (e.g., > 0.9% NaCl) will:Why do wilted flowers revive when placed in fresh water?The van't Hoff factor (i) for a solute that completely dissociates into n particles is:For benzoic acid dimerising in benzene (2 CH₃COOH ⇌ (CH₃COOH)₂), the van't Hoff factor approaches:Inclusion of the van't Hoff factor modifies the boiling point elevation formula to:Experimentally, a solute is found to have a molar mass *lower* than its formula mass. This indicates the solutIn an antifreeze formulation, 35% (v/v) ethylene glycol in water lowers the freezing point of water to about:
0.9% (mass/volume) sodium chloride solution is called the 'normal saline solution' because:Molarity M is defined as:Molality m is defined as:Mole fraction x_A is:Raoult's law for an ideal solution (one component A in solvent S) is:Henry's law for gas dissolution: solubility of a gas (mass m_gas per unit mass of solvent) is:Colligative properties depend on:What is the molarity of a solution containing 5.85 g of NaCl (M.W. = 58.5) in 250 mL of solution?Boiling point elevation: ΔT_b = K_b × m. For 1 molal aqueous urea (K_b = 0.52 K kg/mol), ΔT_b equals:Freezing point depression: ΔT_f = K_f × m. For 0.5 molal NaCl (assume full dissociation, K_f = 1.86), the deprVapour pressure of pure water at 25°C is 23.8 mm Hg. The vapour pressure of a solution with 18 g glucose (M.W.Osmotic pressure π = nRT/V (or CRT for molarity C). What is π for 0.1 M sugar solution at 27°C (R = 0.0821)?The van't Hoff factor i for a strong electrolyte like CaCl2 (full dissociation) is:In ideal solutions, ΔH_mix is:Mass percentage (w/w) of a solution: 12 g sugar in 100 g of solution is:Two solutions are isotonic if:For an azeotrope of HCl and water (boiling at 110°C with 20.2% HCl by mass), the composition and boiling pointMaximum boiling azeotropes are formed by mixtures with:Molality of a solution does not depend on:For 0.5 m solutions of NaCl, KCl, and BaCl2, which gives largest ΔT_f?Pure water boils at 100°C; pure ethanol at 78°C. A 0.5 mole fraction mixture under positive deviation will:Osmotic pressure of 0.1 M Glucose at 27°C is π_g. For 0.1 M NaCl at same T, the osmotic pressure is approximatThe pKa of a weak acid HA is 4.75. Find pH of an equimolar mixture of HA and A⁻:Solubility of N2 in water at 25°C is 6.8 × 10⁻⁴ mol/L at 1 atm partial pressure. By Henry's law, at 5 atm partTwo solutions A (0.1 M urea, π_A) and B (0.1 M NaCl, π_B). Water flows by osmosis:A solution boils at 100.5°C (water at 100). If K_b = 0.52, molality is:Mole fraction of solute in 18% glucose (180 g/mol) by mass in water:Vapour pressure of pure water is 100 (arbitrary units). Add 1 mole non-volatile solute to 9 moles water. New vA solution is:Mole fraction of solute x_B in a binary solution:Molarity M is defined as:Molality m is defined as:Henry's law states partial pressure of a gas above liquid is proportional to:Raoult's law for ideal solution states vapor pressure of solvent:For dilute solutions, lowering of vapor pressure of solvent ΔP / P°_A =Elevation in boiling point ΔT_b for solution of non-volatile solute:Depression in freezing point ΔT_f for non-electrolyte solute:Osmotic pressure π for dilute solution: