Instruction:
Hi guys, in this post I provide previous years questions of chapter solution and collective property for Mht cet mostly. This questions included 2019 questions of mht cet. For more questions plase follow my blog.
#Previous chapter questions links given below
#Past (previous) years questions of entrance exam:
(1)Van't Hoff factor for 0.1M Ba(NO3)2 solution is 2.74, the degree of dissociation is
(A)0.91
(B)0.87
(C)0.74
(D) 87 [MHT-CET 2019]
Ans:
actually, van't Hoff's factor for any reaction ,
then, van't Hoff factor ( i ) = 1 + (n -1)α
where α is the degree of dissociation .
similarly,
now , van't Hoff' factor { i } = 1 - α + α + 2α
2.74 = 1 + 2α
1.74 = 2α
α = 0.87
that's why option (B) is right.
(2) 9 gram ainhydrous oxalic acid (Mol. Wt 90) was dissolved in 9.9 moles of water. If vapour
oressure of pure water 1s PT, the vapour pressure of solution is
(A)L.IP
(B) 0.99P
(C)0.90P
(D)0.IP. [MHT-CET 2019]
Ans:
9 gram anhydrous oxalic acid (Molwt = 90)
was dissolved in 9.9 moles of water. If vapour
pressure of pure water is P4, the vapour
pressure of solution is YOU A.0 0.1.PO B.O
0.90.P CO 11.P, D. 0.99.PO
that's why option (B) is right.
(3) Which of the following sets of solutions of urea (mol. mass. 60 g mol) and sucrose (mol. mass.
342 g mol) is isotonic ? [MHT-CET 2019]
(A)3.0 g/L urea and 17.1 g/L sucrose
(B)3.0 g/Lurea and 3.0 g/L sucrose
(C)9.1 g/L urea and 6.0 g/L sucrose
(D)6.0 g/L urea and 9.0 g/L sucrose
Ans:
Which of the following sets of solutions of
urea (mol. Mass. 60 g mol-1) and sucrose
(mol. Mass.342 g mol-1) is isotonic? A. 3.0 gL1
urea and 17.1 gl°? sucrose B.O 9.1 g/l. urea and
6.0 g/l? sucrose YOU CO 3.0 g/l urea and 3.0
gll sucrose D.O 6.0 gl-urea and9.0 g/l
sucrose
that's why option (A) is right.
(4) 18 gram ghucose (Molar mass 180) is dissolved in 100 ml of water at 300 K. If R 0.0821
L-atm \mol\K what is the osmotic pressure of solution? [MHT-CET 2019]
(A)2.463 atm
(B) 8.21 atm
(C) 24.63 atm
(D) 0.821 atm
Ans:
18 gram glucose (Molecular mass 180) is
dissolved in 100 ml of water at 300 K. IfR =
O.0821 L-atm mol-1K-7 what is the osmotic
pressure of solution? A. 2463 atm YOU B.0
2.463 atm CO 8.21 atm D.O 0.821 atm
that's why option (C) is right.
(5) Which among the following salts, solubility decreases with increase in temperature? [MHT-CET 2019]
(A)KCI
(B) NaCI
(C) NaSO4
(D) NaBr
Ans:
Solubility of NaSO4 increases up to 32.8°C and then it decreases with increases in temperature.
that's why option (C) is right.
(6) The elevation in boiling point of 0.25 molal aqueous solution of a substance is (K-0.52 K Kg \mol). [MHT-CET 2019]
(A)0.13 K
(B)2.08 K
(C)0.50 K
(D)o.15 K
Ans:
that's why option (A) is right.
(7) What is the abnormal molecular mass of benzoic acid when added in benzene?
Given, atomic mass H-1,0-16,C-12)
[MHT-CET 2019]
(A)366
(B) 244
(C)122
(D)61
Ans:
1.244 units
2. In benzene, benzoic acid exist as dimer. So the molecular weight of benzoic acid gets doubled.
(C6H5COOH)2=2×122=244 units .
that's why option (B) is right.
(8) Which of the following properties of liquid increases with increase in temperature? [MHT-CET 2019]
(a)Surface tension
(B) Vapour pressure
(C) Viscosity
(D) Density
Ans:
Surface tension, viscosity and density will decrease with increase in temperature except for vapour pressure
Vapour pressure will increase with increase in temperature.
With increase in temperature, kinetic energy of liquid molecules increases. This increases the number of molecules that change phase from liquid to gas. It increases vapour pressure.
that's why option (B) is right.
(9) ldentify the colligative property among the followings
[MHT-CET 2019]
(A) Boiling point of a solvent
(B) Vapour pressure of a solvent
(C) freezing point of a solvent
(D) Osmotic pressure of a solution
Ans:
The properties of the solutions which depends on the number of particles of the solute but not on the mass of the solute in the solvent are called colligative properties.
Examples:
1) Elevation in boiling point
2) Depression in freezing point
3) Depression in vapour pressure
4) Osmatic pressure
that's why option (C) is right.
(10) What is the mass of sucrose in its 1L solution which is isotonic with 6.6 g\Lof urea? [MHT-CET 2019]
AmCmassH= 1,C= 12, N-14,0- 16)
(A) 37.62 g
(B) 34.2 g
(C)68.2g
(D) 30.1 g
Ans:
Sucrose molar weight 342
moles of urea--0.11
60
43. s of sucrose in 1L isotonic with 6.6 g/L of urea =0.11 x 342= 37.62 g
that's why option (A) is right
(11) Which of the following solutes has highest ∆Tf\m,value in the its 0.05 molal aqueous solution?
[MHT-CET 2019]
(A)Potassium sulphate
(B) Glucose
(C) Aluminium chloride
(D)Ammonium chloride
Ans:
Aluminum chloride
that's why option (C) is right.
(12) Calculate Vant Hoff factor for 0.2 m aqueous solution of KCI which freezes at -0.680 C
(K1.86 Kkg \mol). [MHT-CET 2019]
(A) 6.8
(B) 1.86
(C) 3.72
(D) 1.83
Ans:
option (D) is right.
(13) Which of the following sets of components form homogeneous mixture ? [MHT-CET 2019]
(A)Silver chloride +Water
(B) Sugar +Benzene
(C)Ethyl alcohol+ Water
(D) Phenol+Water
Ans:
The homogenous mixture has all the components in the same phase.Phenol and water are miscible. They both are present in liquid state.Sugar is present in solid-state whereas benzene is present in a liquid state. Thus, they form a heterogeneous mixture.Silver chloride is a white crystalline solid whereas water is in the liquid state thus they form a heterogeneous mixture.Ethyl alcohol and water both are present in liquid state and are polar liquid. Thus, they form a homogenous mixture.
(14) The molarity of urea (molar mass 60 g mor') solution by dissolving 15 g of urea in 500 cm' of water is
[MHT-CET 2018]
(A)2 mol dm
(B)0.5 mol dm-3
(C)0.125 mol dm
(D)o.0005 mol dm
Ans:
The number of moles of urea = Molar mass of urea Mass of urea = 60 g/mol 15 g= 0.25 mol
The volume of solution is 500 cm3× 1000 cm31 L = 0.500 L
The molarity is the ratio of moles to the volume.
Molarity = Volume of solution (in L) Number of moles of solute
Molarity = 0.500 L 0.25 mol
Molarity = 0.5 mol dm −3
that's why option (B) is right.
(15) Molarity is. [MHT-CET 2018]
(A)The number of moles of solute present in 1 dm4 volume of solution
(B) The number of moles of solute dissolved in 1 kg of solvent
(C)The number of moles of solute.dissolved in 1 kg of solution
(D)The number of moles of solute dissolved in 100 dm3 volume of solution
Ans:
Molarity is a unit of concentration measuring the number of moles of a solute per liter of solution. 1 litre is 1dm3.
that's why option (A) is rightright.
(16) The molality of solution containing 15.20 g of urea, (molar mass-60) dissolved in 150 g of water is
[MHT-CET 2017]
(A)1.689 mol /kg
(B)0.1689 mol kg"
(C)0.5922 mol kg
(D)0.2533 mol kg
Ans:
molality = molar mass of urea × mass of water in kg mass of urea
molality = 60 g/mol× 0.150 kg 15.20 g
molality = 1.689 mol/kg
that's why option (A) is right.
(17) Solubility of which among the following solids in water changes slightly with temperature?
[MHT-CET 2017]
(A) KNO
(B) KBr
(C) NaNOs
(D) NaBr
Ans:
option (D) is right.
(18) The osmotic pressure of solution containing 34.2 g of cane sugar (molar mass 342 g mol) in
L of solution at 20° C is (Given, R-0.082 L atm K mo"). [MHT-CET 2017]
(A)2.40 atm
(B) 3.6 atm
(C)2.42atm
(D)0.0024 atm
Ans:
The expression for the osmotic pressure of the solution is shown below.
π=CRT=M×VWRT
Here, π is the osmotic pressure, C is the molar concentration, W is mass of solute, M is the molar mass of solute, V is the volume of the solution in liter, R is the ideal gas constant and T is the absolute temperature.
π= 342 g/mol 34.2 g× 0.082 L atm / mol K× 293 K
π= 2.40 atm
The osmotic pressure of the solution is 2.40 atm.
that's why option (A) is right.
(19) For which among the following equimolar aqueous solutions Van't Hoff factor has the lowest value ?
[MHT-CET 2017]
(A)Aluminium Chloride
(B) Potassium Sulphate
(C)Ammonium Chloride
(D)Urea
Ans:
For the aqueous solution of urea, van't Hoff factor has the lowest value.
Urea is non-electrolyte and does not dissociate in aqueous solution. Hence, Van't Hoff factor is 1.
For aluminium chloride AlCl3, i=4
AlCl3→Al3++3Cl−
For potassium sulphate K2SO4, i=3
K2SO4→2K++SO42−
that's why option (D) is right.
(20) 5.0 g of sodium hydroxide (molar mass 40 g mol) is dissolved in little quantity of water and the
solution is diluted up to 100 ml. What is the molarity of the resulting solution?
[MHT-CET 2016]
(A)0.125 mol dm
(B)1.25 mol dm
(C) 1.0 mol dm
(D)O.1 mol dm"
Ans:
Molarity is a unit of the concentration measuring the number of moles of a solute per litre of solution.
Moles of solute is 405=0.125 moles
Volume of the solution in litres is 100/1000=0.1L
Molarity =0.10.125=1.25mol L=1.25mol dm
that's why option (B) is right.
(21) Identify the compound amongst the following of which 0.1 M aqueous solution has highest boiling point
[MHT-CET 2016]
(A) Sodium chloride
(B) Calcium chloride
(C) Feric chloride
(D) Glucose
Ans:
0.1 M aqueous solution of ferric chloride has the highest boiling point.
The dissociation of one molecule of ferric chloride gives the maximum number of ions (four ions) in the solution.
FeCl3→Fe3++3Cl−
Glucose is a non-electrolyte and it does not undergo dissociation.
The dissociation of one molecule of sodium chloride gives two ions.
The dissociation of one molecule of calcium chloride gives three ions.
Note: The solution which gives the highest number of ions on dissociation will have the highest boiling point.
that's why option (C) is right.
(22) The relation between solubility of a gas in liquid at constant temperature and extemal presure is stated by which law ? [MHT-CET 2016]
(A) van't Hoff Boyle's law
(B)Raoult's law
(C)van't Hof Charles' law
(D)Henry's law
Ans:
Henry Law:
The amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.
Hence, this relates solubility of solute and pressure.
that's why option (D) is right.
(23) What is the volume of water consumed during acid hydrolysis of 1.368 Kg of sucrose?
(Given-molar masses of sucrose342, water 18, density of water= 1 g/cm)
(A)0.072 dm3
(B)0.18 dm3
(C)0.720 dm3
(D)0.018 dm3
[MHT-CET 2015]
Ans:
C12H22O11+H2OH+C6H12O6+C6H12O6
1 mol of sucrose requires 1 mol of H2O.
1.368 g of C12H22O11 has 3421.368×103=4 moles.
4 moles of sucrose requires the same number of moles of H2O.
Molar mass of H2O=18 g/mol
So, mass of H2O required =18×4=72 gm of H2O.
The density of water =1g/cm3.
So, volume of water required =densitymass=172=72cm3 or 0.072 dm3
that's why option (A) is right.
(24) Molarity is defined as
[MHT-CET 2015]
(A) the number of moles of solute dissolved in one dm3 of the solution
(B) the number of moles of solute dissolved in 1 kg of solvent
(C) the number of moles of solute dissolved in 1 dm3 of the solvent
(D) the number of moles of solute dissolved in 100 ml of the solvent
Ans:
Molarity is a unit of concentration measuring the number of moles of a solute per liter of solution. 1 litre is 1dm3.
that's why option (A) is right.
(25) Which among the following alloys is used in making instruments for electrical measurements
(A)Spiegeleisen
(B)Stainless steel
(C)Duralumdm
(D) Mangain
[MHT-CET 2015]
Ans:
Manganin foil and wire is used in the manufacture of resistors, particularly ammeter shunts, because of its virtually zero temperature coefficient of resistance value and long term stability. So it is used in making electrical instruments.
that's why option (D) is right.
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 years questions of entrance (Mht cet) exam){kind=link}
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