JEE Chemistry Solutions MCQs Set A

Question. “The importance of many pure substance in life depends on their composition.” Which of the following statement justify the above fact?
(a) All of the above.
(b) Concentration above 1.5 ppm can be poisonous
(c) 1.5 ppm of fluoride ions causes tooth decay
(d) 1 ppm of fluoride ions in water prevents tooth decay.

Answer: A

Question. Which of the following fluoride is used as rat poison?
(a) NaF
(b) CaF₂
(c) KF
(d) MgF₂

Answer: A

Question. Most of the processes in our body occur in
(a) liquid solution
(b) colloidal solution
(c) solid solution
(d) gaseous solution

Answer: A

Question. The term homogenous mixtures signifies that
(a) both composition and properties are uniform throughout the mixture
(b) its properties are uniform throughout the mixture
(c) its composition is uniform throughout the mixture
(d) neither composition nor properties are uniform throughout the mixture

Answer: A

Question.  Which of the following mixture is(are) called solution?
(i) water + ammonia   (ii) water + acetone
(iii) acetone + alcohol (iv) hexane + water
(a) (i), (ii) and (iii)
(b) (i) and (iv)
(c) (i), (iii) and (iv)
(d) (ii) and (iii)

Answer: A

Question. Which of the following is a quantitative description of the solution?
(a) Molar
(b) Concentrated
(c) Dilute
(d) Saturated

Answer: A

Question.  When a solute is present in trace quantities the following expression is used
(a) Parts per million
(b) Milligram percent
(c) Gram per million
(d) Microgram percent

Answer: A

Question. Molarity of liquid HCl will be, if density of solution is 1.17 gm/cc
(a) 32.05
(b) 42.10
(c) 36.5
(d) 18.25

Answer: A

Question.  1 M, 2.5 litre NaOH solution is mixed with another 0.5 M, 3 litre NaOH solution. Then find out the molarity of resultant solution
(a) 0.73 M
(b) 0.80 M
(c) 1.0 M
(d) 0.50 M

Answer: A

Question. An X molal solution of a compound in benzene has mole fraction of solute equal to 0.2. The value of X is
(a) 3.2
(b) 2
(c) 14
(d) 1.4

Answer: A

Question. The molarity of the solution containing 7.1 g of Na₂SO₄ in 100 ml of aqueous solution is
(a) 0.5 M
(b) 0.05 M
(c) 2 M
(d) 1 M

Answer: A

Question. The vapour pressure of pure benzene at 25°C is 640 mm Hg and that of solution of solute A is 630 mm Hg. The molality of solution is
(a) 0.2 m
(b) 0.5 m
(c) 0.4 m
(d) 0.1 m

Answer: A

Question. 4.0 g of NaOH is dissolved in 100 ml solution. The normality of the solution is
(a) 1.0 N
(b) 0.5 N
(c) 0.1 N
(d) 4.0 N

Answer: A

Question. The molarity of pure water is
(a) 55.6 M
(b) 50 M
(c) 18 M
(d) 100 M

Answer: A

Question. An aqueous solution of glucose is 10% in strength. The volume in which 1 g mole of it is dissolved, will be
(a) 1.8 litre
(b) 0.9 litre
(c) 9 litre
(d) 8 litre

Answer: A

Question. 1 g of NaCl is dissolved in 106g of the solution. Its concentration is
(a) 10 ppm
(b) 0.1 ppm
(c) 100 ppm
(d) 1 ppm

Answer: A

Question. On adding a solute to a solvent having vapour pressure 0.80 atm, vapour pressure reduces to 0.60 atm. Mole fraction of solute is
(a) 0.25
(b) 0.50
(c) 0.75
(d) 0.33

Answer: A

Question. 2.5 litres of NaCl solution contain 5 moles of the solute. What is the molarity?
(a) 2 molar
(b) 12.5 molar
(c) 5 molar
(d) 2.5 molar

Answer: A

Question. The mole fraction of the solute in one molal aqueous solution i
(a) 0.018
(b) 0.036
(c) 0.009
(d) 0.027

Answer: A

Question. 25ml of a solution of barium hydroxide on titration with a 0.1 molar solution of hydrochloric acid gave a titre value of 35ml. The molarity of barium  hydroxide solution was
(a) 0.07
(b) 0.28
(c) 0.14
(d) 0.35

Answer: A

Question. Mole fraction of the solute in a 1.00 molal aqueous solution is
(a) 0.0177
(b) 1.7700
(c) 0.1770
(d) 0.0344

Answer: A

Question. What is the normality of a 1 M solution of H₃PO₄ ?
(a) 3.0 N
(b) 1.0 N
(c) 0.5 N
(d) 2.0 N

Answer: A

Question. The volume of 4 N HCl and 10 N HCl required to make 1 litre of 6 N HCl are
(a) 0.67 litre of 4 N HCl and 0.33 litre of 10 N HCl
(b) 0.80 litre of 4 N HCl and 0.20 litre of 10 N HCl
(c) 0.50 litre of 4 N HCl and 0.50 litre of 10 N HCl
(d) 0.75 litre of 10 N HCl and 0.25 litre of 4 N HCl

Answer: A

Question. Molarity of H₂SO₄ is 18 M. Its density is 1.8 g/ml. Hence molality is
(a) 500
(b) 36
(c) 200
(d) 18

Answer: A

Question. 200 ml of water is added to 500 ml of 0.2 M solution. What is the molarity of this diluted solution ?
(a) 0.1428 M
(b) 0.2897 M
(c) 0.5010 M
(d) 0.7093 M

Answer: A

Question. How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0M HNO₃ ? The concentrated acid is 70% HNO₃
(a) 45.0 g conc. HNO₃
(b) 70.0 g conc. HNO₃
(c) 90.0 g conc. HNO₃
(d) 54.0 g conc. HNO₃

Answer: A

Question. For preparing 0.1 N solution of a compound from its impure sample of which the percentage purity is known, the weight of the substance required will be
(a) More than the theoretical weight
(b) Same as the theoretical weight
(c) Less than the theoretical weight
(d) None of these

Answer: A

Question. A solution made by dissolving 40 g NaOH in 1000 g of water is
(a) 1 molal
(b) 1 molar
(c) 1 normal
(d) None of these

Answer: A

Question. Which of the following concentration terms is/are ndependent of temperature?
(a) Molality and mole fraction
(b) Molality only
(c) Molarity and mole fraction
(d) Molality and normality

Answer: A

Question. A solution is prepared by dissolving 10 g NaOH in 1250 mL f a solvent of density 0.8 mL/g. The molality of the solution in mol kg^–1 is
(a) 0.25
(b) 0.008
(c) 0.2
(d) 0.0064

Answer: A

Question. Which of the following units is useful in relating concentration of solution with its vapour pressure?
(a) mole fraction
(b) mass percentage
(c) parts per million
(d) molality

Answer: A

Question. Which of the following concentration unit is independent of temperature ?
(a) Molality
(b) Molarity
(c) Normality
(d) Formality

Answer: A

Question. Which of the following factor do not affect solubility of solid solute in liquid ?
(a) Pressure
(b) All of these
(c) Temperature
(d) Nature of solute

Answer: A

Question. When a solid solute is added to the solvent, some solute dissolves and its concentration increases in solution. This process is known as ______. Some solute particles in solution collide with the solid solute particles and get separated out of solution. This process is known as ______.
(a) Dissolution, crystallization
(b) Saturation, crystallization
(c) Dissolution, saturation
(d) Crystallization, dissolution

Answer: A

Question. Which of the following statements is incorrect?
(a) The minimum amount of solute dissolved in a given amount of solvent is its solubility
(b) The solution which is in dynamic equilibrium with undissolved solute is the saturated solution
(c) An unsaturated solution is one in which more solute can be dissolved at the same temperature
(d) A solution in which no more solute can be dissolved at the same temperature and pressure is called a saturated solution

Answer: A

Question. On dissolving sugar in water at room temperature solution feels cool to touch. Under which of the following cases dissolution of sugar will be most rapid ?
(a) Powdered sugar in hot water
(b) Powdered sugar in cold water
(c) Sugar crystals in hot water.
(d) Sugar crystals in cold water

Answer: A

Question. The statement “If 0.003 moles of a gas are dissolved in 900 g of water under a pressure of 1 atmosphere, 0.006 moles will be dissolved under a pressure of 2 atmospheres”, illustrates
(a) Henry’s law
(b) Raoult’s law
(c) Graham’s law
(d) Dalton’s law of partial pressure

Answer: A

Question. According to Henry’s law, the amount of gas that will dissolve in blood plasma or any other liquid is determined by which of these factor?
(a) Solubility of the gas in the liquid.
(b) The total pressure of the gas mixture
(c) pH of the liquid
(d) The osmotic pressure of the gas mixture

Answer: A

Question. Henry’s law constant of oxygen is 1.4 × 10^–3 mol. lit^–1. atm^–1 at 298 K. How much of oxygen is dissolved in 100 ml at 298 K when the partial pressure of oxygen is 0.5 atm?
(a) 2.24 mg
(b) 3.2 g
(c) 1.4 g
(d) 22.4 mg

Answer: A

Question. At equillibrium the rate of dissolution of a solid solute in a volatile liquid solvent is ______.
(a) equal to the rate of crystallisation
(b) zero
(c) greater than the rate of crystallisation
(d) less than the rate of crystallisation

Answer: A

Question. A beaker contains a solution of substance ‘A’. Precipitation of substance ‘A’ takes place when small amount of ‘A’ is added to the solution. The solution is ______.
(a) supersaturated
(b) concentrated
(c) saturated
(d) unsaturated

Answer: A

Question. Maximum amount of a solid solute that can be dissolved in a specified amount of a given liquid solvent does not depend upon __________.
(a) Pressure
(b) Temperature
(c) Nature of solute
(d) Nature of solvent

Answer: A

Question. Low concentration of oxygen in the blood and tissues of people living at high altitude is due to
(a) low atmospheric pressure
(b) high atmospheric pressure
(c) both low temperature and high atmospheric pressure
(d) low temperature

Answer: A

Question. Value of Henry's constant K_H _______.
(a) increases with increase in temperature.
(b) decreases with increase in temperature.
(c) remains constant
(d) first increases then decreases

Answer: A

Question. The value of Henry's constant K_H is _______.
(a) greater for gases with lower solubility
(b) greater for gases with higher solubility
(c) constant for all gases
(d) not related to the solubility of gases

Answer: A

Question. Which of the followingfactor(s) affect the solubility of a gaseous solute in the fixed volume of liquid solvent ?
(i) Nature of solute (ii) Temperature (iii) Pressure
(a) (i) and (iii) at constant T
(b) (i) and (ii) at constant P
(c) (ii) and (iii) only
(d) (iii) only

Answer: A

Question. Which is an application of Henry’s law?
(a) Soft drinks (soda)
(b) Bottled water
(c) Spray paint
(d) Filling up atire

Answer: A

Question. Scuba divers may experience a condition called ______. To avoids this, the tanks used by scuba divers are filled with air diluted with _____
(a) Bends, Helium
(b) Cramps, Nitrogen
(c) Migrains, Hydrogen
(d) Nausea, Oxygen

Answer: A

Question. People living at high attitudes often reported with a problem of feeling weak and inability to think clearly. The reason for this is
(a) at high altitudes the partial pressure of oxygen is less than at the ground level
(b) at high altitudes the partial pressure of oxygen is more than at the ground level
(c) at high altitudes the partial pressure of oxygen is equal to at the ground level
(d) None of these

Answer: A

Question. ____ a contemporary of Henry concluded independently that solubility of a gas in a liquid solution is a function of ____ of the gas.
(a) Dalton, partial pressure
(b) Mosley, partial pressure
(c) Dalton, temperature
(d) Mosley, temperature

Answer: A

Question. Iodine and sulphur dissolve in
(a) carbon disulphide
(b) water
(c) benzene
(d) ethanol

Answer: A

Question. The liquids at a given temperature vapourise and under equilibrium conditions the pressure exerted by the vapours of the liquid over the liquid phase is called
(a) vapour pressure
(b) atmospheric pressure
(c) osmotic pressure
(d) hydrostatic pressure

Answer: A

Question. Which of the following fluoride is used as rat poison?
(a) NaF
(b) KF
(c) CaF₂
(d) MgF₂

Answer: A