JAMB - Chemistry (1992)

  • 1
    There is a large temperature interval between the melting point and the boiling point of a metal because?
    პასუხი
    (C)
    melting does not break the metalic bond but boiling does
  • 2
    How many moles of (H+) are there in 1 dm3 of 0.5 M solution of H2SO4?
    პასუხი
    (B)
    1.0 moles
  • 3
    wH2SO4 + xAI(OH)3 → yH2O + = zAI2(SO4)3. The respective values of w.x.y and z in the equation above are?
    პასუხი
    (C)
    3,2,6 and 1
  • 4
    A given mass of gas occupies 2 dm3 at 300k. At what temperature will its volume be doubled keeping the pressure constant?
    პასუხი
    (D)
    600 k
  • 5
    Which of the following is a measure of the average kinetic energy of the molecules of a substance?
    პასუხი
    (D)
    Temperature
  • 6
    If 100 cm3 of oxygen pass through a porous plug in 50 seconds, the time taken for the same volume of hydrogen to pass through the same porous plug is?



    (O = 16, H = 1)
    პასუხი
    (B)
    12.5 s
  • 7
    An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the?
    პასუხი
    (D)
    number of collisions between the gas molecules and the walls of the container
  • 8
    The nucleus of the isotope tritium, contains?
    პასუხი
    (C)
    two neutrons and one proton
  • 9
    How many lone pairs of electron are there on the central atom of the H2O molecules?
    პასუხი
    (B)
    2
  • 10
    147N + X → 178O + 11 H. In the above reaction, X is a?
    პასუხი
    (B)
    helium atom
  • 11
    The pollutants that are likely to be present in an industrial environment are?
    პასუხი
    (A)
    H2S,SO2 and oxides of nitrogen
  • 12
    Four elements P,Q,R and S have 1,2,3, and 7 electrons in their outermost shells respectively. The element which is unlikely to be a metal is?
    პასუხი
    (D)
    S
  • 13
    Which of the following gases dissolves in water vapour to produce acid rain during rainfall?
    პასუხი
    (D)
    Sulphur (IV) oxide
  • 14
    Water for town supply is chlorinated to make it free from?
    პასუხი
    (B)
    bacteria
  • 15
    On which of the following is the solubility of a gaseous substance dependent? I. Nature of solvent II. Nature of solute III. Temperature IV. Pressure
    პასუხი
    (A)
    I, II, III and IV
  • 16
    An emulsion paint consists of ?
    პასუხი
    (B)
    liquid particles dispersed in liquid
  • 17
    A sample of orange juice is found to have a pH of 3.80. What is he concentration of the hydroxide ion in the juice?
    პასუხი
    (B)
    6.3 x 10-11
  • 18
    Arrange HCI, CH3COOH, C6H5CH3 in order of increasing conductivity.
    პასუხი
    (C)
    C6H5CH3, CH3COOH, HCI
  • 19
    How many grams of H2SO4 are necessary for the preparation of 0.175 dm3 of M 6.00 M H2SO4?

    (S = 32.06, O = 16.00 H = 1.00)
    პასუხი
    (B)
    103.0 g
  • 20
    Copper (II) tetraoxosulphate (VI) solution is electrolyzed using carbon electrodes. Which of the following are produced at the anode and cathode respectively ?
    პასუხი
    (B)
    Oxygen and copper
  • 21
    Calculate the mass, in kilograms, of magnesium produced by the electrolysis of magnesium (II) chloride in a cell operating for 24 hours at 500 amperes.
    პასუხი
    (B)
    5.4
  • 22
    S2O2-3 + I2 → S2O62- + 2I-. In reaction above, the oxidizing agent is?
    პასუხი
    (B)
    I2
  • 23
    \(MnO_2 + 2CI^- + 4H^+ → Mn^{2+} + CI_2 + 2H_2O\).
    The changes in oxidation numbers when the manganese, chloride, and hydrogen ions react according to the above equation are respectively?
    პასუხი
    (C)
    -2, 1, 0
  • 24
    In which of the following is the entropy change positive?
    პასუხი
    (A)
    H2O(I) → H2O(g)
  • 25
    In what way is equilibrium constant for the forward reaction related to that of the reversed reaction?
    პასუხი
    (B)
    The product of the two is expected to be one
  • 26
    Which of the following equilibria shows little or no net reaction when the volume of the system is decreased?
    პასუხი
    (D)
    ZnO(s) + CO2(g) ≈ ZnCO3(g)
  • 27
    For a general equation of the nature xP + yQ ≈ mR + nS, the expression for the equilibrium constant is?
    პასუხი
    (C)
    (R)m (S)n / (p)x (Q)y
  • 28
    Which of these statements is TRUE about carbon (IV) oxide?
    პასუხი
    (C)
    It is very soluble in water
  • 29
    Which of the following combination of gases is used for metal welding? i. Oxygen and ethyne, ii. Hydrogen and ethyne, iii. Hydrogen and oxygen, iv. Ethyne, hydrogen and oxygen.
    პასუხი
    (C)
    i and iii
  • 30
    Which of the following oxides of nitrogen is unstable in air?
    პასუხი
    (B)
    NO
  • 31
    The gas formed when ammonium trioxonitrate (V) is heated with sodium hydroxide is?
    პასუხი
    (D)
    ammonium
  • 32
    The gas formed when ammonium trioxonitrate (V) is heated with sodium hydroxide is?
    პასუხი
    (D)
    ammonia
  • 33
    Safety matches contain sulphur and the following except?
    პასუხი
    (A)
    sodium chloride
  • 34
    Addition of an aqueous solution of a salt gives a white precipitate. The salt is likely to be a?
    პასუხი
    (B)
    carbonate
  • 35
    Sodium hydroxide solution can be conveniently stored in a container made of?
    პასუხი
    (D)
    copper
  • 36
    Which of the following is NOT used as a raw material in the Solvay process?
    პასუხი
    (D)
    Sodium trioxocarbonate (IV)
  • 37
    Duralumin consists of aluminium, copper, ?
    პასუხი
    (D)
    manganese and magnesium
  • 38
    CaOs + H2O(l) → Ca(OH)2(s) ΔH -65 kj. The process represented by the above equation is known as?
    პასუხი
    (B)
    slaking
  • 39
    The carbon atoms in ethene are?
    პასუხი
    (C)
    sp2 hybridized
  • 40
    Which of the following compounds reacts with sodium metal as well as silver and copper salts ?
    პასუხი
    (C)
    CH3C Ξ CH
  • 41
    Which of the following are isomers?
    პასუხი
    (A)
    Ethanol and dimethyl ether
  • 42
    The functional group present in an organic compound which gives bubbles on treatment with a saturated solution of NaHCO3 is?
    პასუხი
    (D)
    carboxyl group
  • 43
    An organic compound containing 40.1% carbon and 6.6% hydrogen has an empirical formula of?
    პასუხი
    (C)
    CH2O
  • 44
    The characteristics reaction of carbonyl compounds is?
    პასუხი
    (C)
    addition
  • 45
    Alkanals can be differentiated from alkanones by reaction with?
    პასუხი
    (D)
    Tollen's reagent
  • 46
    An example of a polysaccharides is?
    პასუხი
    (D)
    starch
  • 47

    In the experiment above. Z can be

    პასუხი
    (C)
    a solution of sodium trioxonitrate (V) and ammonium chloride
  • 48

    Which of the following compounds is a secondary alkanol?

    პასუხი
    (A)
    A
  • 49
    A given mass of gas occupies 2 dm2 at 300k. At what temperature will its volume be doubled keeping the pressure constant?
    პასუხი
    (D)
    600k
  • 50
    Which of the following is a measure of the average kinetic energy of the molecules of a substance?
    პასუხი
    (D)
    temperature