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JEE Main Chemistry · Some Basic Concepts of Chemistry · Set 3 (Q61-90)

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  1. 61.
    of an organic compound containing C, and on combustion yields and . If one mol of compound weighs 60 , then molecular formula of the compound is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  2. 62.
    What is the mass ratio of ethylene glycol (, molar mass = 62 g/mol) required for making 500 g of 0.25 molal aqueous solution and 250 mL of 0.25 molar aqueous solution ?
    1. (1)1 : 1
    2. (2)3: 1
    3. (3)2 : 1
    4. (4)1 : 2
  3. 63.
    of a mixture of and requires of to react completely. The percentage of calcium oxide in the mixture is approximately (Given: molar mass of )
    1. (1)52.6
    2. (2)55.1
    3. (3)44.9
    4. (4)47.4
  4. 64.
    What is the quantity of hydrogen gas liberated when sodium reacts with excess ethanol?
    (Given At. mass of )
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  5. 65.
    At S.T.P. the density of vapour in will be nearest to
    1. (1)6.87
    2. (2)3.42
    3. (3)10.26
    4. (4)4.57
  6. 66.
    Excess of silver nitrate solution is added to . of Pentaaquachloro chromium(III) chloride solution. The mass of silver chloride obtained in grams is [Atomic mass of silver is 108 .]
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  7. 67.
    Density of 3 M NaCl solution is . The molality of the solution is:
    1. (1)1.79 m
    2. (2)2.79 m
    3. (3)2 m
    4. (4)3 m
  8. 68.
    The number of atoms in 4.25 of is approximately
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  9. 69.
    Combustion of of a gaseous hydrocarbon gives of and of water vapour under the same conditions. The molecular formula of the hydrocarbon is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  10. 70.
    The mass of precipitated when a solution containing of is added to a solution containing of is [Atomic mass of , Atomic mass of
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  11. 71.
    6. molecules of urea are present in 100 of its solution. The concentration of solution is
    1. (1)0.001
    2. (2)0.1
    3. (3)0.02
    4. (4)0.01
  12. 72.
    The number of moles of hydrogen that can be added to 1 mole of an oil is the highest in
    1. (1)linseed oil
    2. (2)groundnut oil
    3. (3)sunflower seed oil
    4. (4)mustard oil.
  13. 73.
    An organic compound contains C, H and S. The minimum molecular weight of the compound containing 8% sulphur is: (atomic weight of S = 32 amu)
    1. (1)300 g
    2. (2)400 g
    3. (3)200 g
    4. (4)600 g
  14. 74.
    of oxygen contains as many atoms as in
    1. (1) of hydrogen
    2. (2) of hydrogen
    3. (3) of hydrogen
    4. (4) of hydrogen
  15. 75.
    A 5-molar solution of is diluted from llitre to a volume of 10litres, the normality of the solution will be
    1. (1)1
    2. (2)0.1
    3. (3)5
    4. (4)0.5
  16. 76.
    In an organic compound of molar mass 108 g C, H and N atoms are present in 9 : 1 : 3.5 by weight. Molecular formula can be:
    1. (1)
    2. (2)N
    3. (3)
    4. (4)
  17. 77.
    Using the rules for significant figures, the correct answer for the expression will be:
    1. (1)0.005613
    2. (2)0.00561
    3. (3)0.0056
    4. (4)0.006
  18. 78.
    Nitrogen can be estimated by Kjeldah's method for which of the following compound?
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  19. 79.
    If a rocket runs on a fuel ( ) and liquid oxygen, the weight of oxygen required and released for every litre of fuel respectively are: (Given: density of the fuel is 0.756 g/mL)
    1. (1)1188 g and 1296 g
    2. (2)2376 g and 2592 g
    3. (3)2592g and 2376 g
    4. (4)3429 g and 3142 g
  20. 80.
    25 mL of the given HCl solution requires 30 mL of 0.1 M sodium carbonate solution. What is the volume of this HCl solution required to titrate 30 mL of 0.2 M aqueous NaOH solution?
    1. (1)25 mL
    2. (2)75 mL
    3. (3)50 mL
    4. (4)12.5 mL
  21. 81.
    What is the percentage of carbon in urea? (At. mass : )
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  22. 82.
    Round the number 234555359 to 3 significant figures.
    1. (1)234000000
    2. (2)234000
    3. (3)235000000
    4. (4)234500000
  23. 83.
    20.0 g of a magnesium carbonate sample decomposes on heating to give carbon-dioxide and 8.0 g magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample? (Atomic weight of )
    1. (1)75
    2. (2)96
    3. (3)60
    4. (4)84
  24. 84.
    One mole of carbon atom weighs 12 g , the number of atoms in it is equal to, (Mass of carbon-12 is )
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  25. 85.
    The molarity of Cl¯ in an aqueous solution which was (w/V) 2% NaCl, 4% and 6% Cl will be
    1. (1)0.342
    2. (2)0.721
    3. (3)1.12
    4. (4)2.18
  26. 86.
    An organic compound gives 0. 220 g of and 0.126 g of O on complete combustion. If the % of carbon is 24 then the % of hydrogen is __________x . (Nearest integer)
  27. 87.
    The complete combustion of 0.492 g of an organic compound containing 'C', 'H' and 'O' gives 0.793g of and 0.442 g of O. The percentage of oxygen composition in the organic compound is ____________- (nearest integer)
  28. 88.
    Fortification of food with iron is done using . The mass in grams of the required to achieve 12 ppm of iron in 150 kg of wheat is (Nearest integer)
    [Given: Molar mass of and and O respectively are 56,32 and ]
  29. 89.
    When 81.0 g of aluminium is allowed to react with 128.0 g of oxygen gas, the mass of aluminium oxide produced in grams is - (Nearest integer) Given : Molar mass of Al is Molar mass of O is
  30. 90.
    On complete combustion of 0.492 g of an organic compound containing C, H and O, 0.7938 g of and 0.4428 g of O was produced. The % composition of oxygen in the compound is_____