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JEE Main Chemistry · Some Basic Concepts of Chemistry · Set 1 (Q1-30)

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  1. 1.
    How many moles of magnesium phosphate, will contain 0.25 mole of oxygen atoms?
    1. (1)0.02
    2. (2)3.125 ×
    3. (3)1.25 ×
    4. (4)2.5 ×
  2. 2.
    An element, has the following isotopic composition:
    : 90% : 8.0% : 2.0% The weighted average atomic mass of the naturally occurring element is closest to
    1. (1)201 amu
    2. (2)202 amu
    3. (3)199 amu
    4. (4)200 amu
  3. 3.
    Which of the following is the most accurate measurement?
    1. (1)9 m
    2. (2)9.0m
    3. (3)9.00m
    4. (4)9.000m
  4. 4.
    The masses of carbondioxide and water (ing) respectively formed during complete combustion of of glucose at STP are
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  5. 5.
    of monobasic acid requires of sodium hydroxide solution whose normality is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  6. 6.
    Temperature of in Fahrenheit and Kelvin scale respectively are
    1. (1) and 298.15 K
    2. (2) and 298.15 K
    3. (3) and
    4. (4) and
  7. 7.
    Which of the following have same number of significant figures?
    (A) 0.00253
    (B) 1.0003
    (C) 15.0
    (D)163
    Choose the correct answer from the options given below
    1. (1)A, B and C only
    2. (2)C and D only
    3. (3)B and C only
    4. (4)A, C and D only
  8. 8.
    of acetic acid is completely neutralized using a standard solution of . The volume of ethane obtained at STP after the complete electrolysis of the resulting solution is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  9. 9.
    Which of the following is not a compound?
    1. (1)Common salt
    2. (2)Marble
    3. (3)Sugar
    4. (4)Coal
  10. 10.
    The volume of 1 mole of any pure gas at standard temperature and pressure is always equal to
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  11. 11.
    The density of 2 M aqueous solution of NaOH is . The molality of the solution is [Given that molecular mass of ]
    1. (1)1.20 m
    2. (2)1.56 m
    3. (3)1.67 m
    4. (4)1.32 m
  12. 12.
    The molarity of the solution containing 2.8% (mass / volume) solution of KOH is: (Given atomic mass of K = 39) is:
    1. (1)0.1 M
    2. (2)0.5 M
    3. (3)0.2 M
    4. (4)1 M
  13. 13.
    Vapour density of a metal chloride is 83 . If equivalent weight of the metal is 6 , its atomic weight will be………….
    1. (1)12
    2. (2)24
    3. (3)18
    4. (4)60
  14. 14.
    of dihydrogen is made to react with of dichlorine to form hydrogen chloride. The volume of hydrogen chloride formed at and 1 bar pressure is
    1. (1)
    2. (2)
    3. (3)
    4. (4).
  15. 15.
    Magnetite can be reduced with to yield iron metal and carbon dioxide. Calculate the mass of magnetite (in ) needed to obtain of iron if the process is efficient.
    [Atomic weight of and are and , respectively]
    1. (1)15.5
    2. (2)5.5
    3. (3)17.0
    4. (4)6.9
  16. 16.
    1 gram of sodium hydroxide was treated with 25 mL of 0.75 M HCl solution, the mass of sodium hydroxide left unreacted is equal to
    1. (1)750 mg
    2. (2)250 mg
    3. (3)0 mg
    4. (4)200 mg
  17. 17.
    What mass of pure will be required to neutralise 50 mL of 0.5 M HCl solution according to the following reaction?

    [Calculate upto second place of decimal point]
    1. (1)9.50 g
    2. (2)1.25 g
    3. (3)1.32 g
    4. (4)3.66 g
  18. 18.
    Excess of carbon dioxide is passed through of calcium hydroxide solution. After the completion of the reaction, the solution was evaporated to dryness. The solid calcium carbonate was completely neutralised with hydrochloric acid. The volume of hydrochloric acid required is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  19. 19.
    Amongst the following, identify the species with an atom in +6 oxidation state:
    1. (1)
    2. (2)[Cr(CN)]
    3. (3)
    4. (4)
  20. 20.
    In the final answer of the expression . The number of significant figures is
    1. (1)1
    2. (2)2
    3. (3)3
    4. (4)4
  21. 21.
    of methane was burnt completely in the presence of oxygen. The liberated gases were passed into a solution containing of . The weight of white precipitate obtained was 500 . What is the value of (in )? (Given : )
    1. (1)16
    2. (2)80
    3. (3)160
    4. (4)120
  22. 22.
    The weight percentage of and in a hydrocarbon is in the ratio of . What is its empirical formula?
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  23. 23.
    On complete combustion 1.0 g of an organic compound gave 1.46 g of and 0.567 g of . The empirical formula mass of compound is g. (Given molar mass in )
    1. (1)60
    2. (2)45
    3. (3)30
    4. (4)15
  24. 24.
    Which one of the following pairs of compounds illustrates the law of multiple proportions?
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  25. 25.
    80 mL of a hydrocarbon on mixing with 264 mL of oxygen in a closed U-tube undergoes complete combustion. The residual gases after cooling to 273 K occupy 224 mL. When the system is treated with KOH solution, the volume decreases to 64 mL. The formula of the hydrocarbon is:
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  26. 26.
    In the balanced equation of the following reaction, the ratio of is a
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  27. 27.
    In basic medium oxidizes to form and itself changes into . The volume of 0.154 required to react with 40 mL of 0.25 is ____ml
    (Rounded-off to the nearest integer)
  28. 28.
    20 mL of 2 M NaOH solution is added to 400 mL of 0.5 M NaOH solution. The final
    concentration of the solution is . (Nearest integer)
  29. 29.
    Some amount of dichloromethane () is added to 671.141 mL of chloroform () to prepare 2.M solution of (DCM).
    The concentration of DCM is ______ ppm (by mass).
    Given: Atomic mass : C = 12; H : 1; Cl = 35.5 density of = 1.
  30. 30.
    The mole fraction of a solute in a molal aqueous solution___
    (Round off to the Nearest Integer) [Given: Atomic masses: H: .