JAMB - Chemistry (2009)

  • 1
    A mixture of sugar and sulphur can be separated by?
    პასუხი
    (C)
    dissolution in water, filtration and evaporation
  • 2
    Which of the following is a physical change?
    პასუხი
    (A)
    Freezing ice cream
  • 3
    The percentage of water of crystallization in ZnSO\(_4\).7H\(_2\)O is?
    [Zn = 65, S = 32, O = 16, H = 1]
    პასუხი
    (B)
    44%
  • 4
    0.0075 mole of calcium trioxocarbonate (IV) is added to 0.015 mole of a solution of hydrochloric acid. The volume of gas evolved at s.t.p is?
    [Molar volume of a gas at s.t.p = 22.4 dm3]
    პასუხი
    (B)
    168cm3
  • 5
    A gas exerts pressure on its container because?
    პასუხი
    (A)
    the molecules of a gas collide with the walls of the container
  • 6
    The basic assumption in the kinetic theory of gases that the collisions of the gaseous molecules are perfectly elastic implies that the?
    პასუხი
    (C)
    gaseous molecules will continue their motion indefinitely
  • 7
    If an atom is represented as \( _{11}^{23}X \), which of the following deduction is correct?
    პასუხი
    (D)
    it is an alkali metal
  • 8
    Cathode rays causes an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays?
    პასუხი
    (D)
    travel in straight lines
  • 9
    Which quantum number divides shells into orbitals?
    პასუხი
    (B)
    Arzimuthal
  • 10
    The type of bonding in \({Cu(NH_3)_4}^2\)+ is?
    პასუხი
    (A)
    coordinate covalent
  • 11
    The mixture of gases used in a photographer's flash tube is?
    პასუხი
    (B)
    krypton and xenon
  • 12
    When sodium trioxocarbonate (IV) decahydrate loses its water of crystallization to the atmosphere, the process is?
    პასუხი
    (B)
    efflorescence
  • 13
    Water can be obtained as the only product during the?
    პასუხი
    (C)
    combustion of hydrogen
  • 14
    If 10.5g of lead (II) trioxonitrate (V) is dissolved in 20cm3 of distilled water at 18oC, the solubility of the solute in mol dm-3 is
    [Pb = 207, N = 14, O = 16]
    პასუხი
    (A)
    1.60
  • 15
    For a given solute, the concentration of its saturated solution in different solvents are
    პასუხი
    (B)
    different at the same temperature
  • 16
    The major source of oxides of nitrogen is from the burning of
    პასუხი
    (C)
    fuel
  • 17
    The acid used in electrolysis of water is dilute?
    პასუხი
    (C)
    H2SO4
  • 18
    What volume of 1.5M solution of KOH would contain 0.045 moles
    პასუხი
    (B)
    30.00 cm3
  • 19
    The salt formed from a reaction between citric acid and sodium hydroxide in solution will be?
    პასუხი
    (B)
    basic
  • 20
    The colour changes observed when testing for reducing agents using acidified potassium heptaoxodichromate (VI) solution is?
    პასუხი
    (B)
    orange to green
  • 21
    The oxidation state of Cr in K\(_2\)Cr\(_2\)O\(_7\) is?
    პასუხი
    (B)
    +6
  • 22
    Which of the following metals is purified commercially by electrolysis?
    პასუხი
    (D)
    Cu
  • 23
    What current will deposit 3.25g of zinc in 2hrs?
    [Zn = 65, F = 96500 mol-]
    პასუხი
    (C)
    1.34A
  • 24
    C(s) + H2O(g) → H2(g) + CO2(g)
    ΔG for the reaction above at 1300k is -43KJ. At this temperature, the reaction is?
    პასუხი
    (C)
    feasible
  • 25
    Two equal bulbs, one containing ammonia and the other nitrogen are opened mouth - to - mouth to each other at room temperature. The entropy in the mixture of gases is likely to?
    პასუხი
    (B)
    increase
  • 26

    In the diagram above, which of the curves represents the evolution of oxygen with time in the equation 2KClO3(s) → 2KCl(s) + 3O2(g)?

    პასუხი
    (D)
    R
  • 27
    A catalyst increase the rate of a chemical reaction by providing a path that?
    პასუხი
    (C)
    lowers the activation energy
  • 28
    CuO(s) + H\(_2\)(g) ↔ Cu(s) + H\(_2\)O(g)
    What is the effect of increasing the pressure on the equilibrium reaction above?
    პასუხი
    (C)
    There is no effect
  • 29
    The equilibrium of an endothermic reaction which proceeds with an increase in volume can be shifted in the reverse direction by
    პასუხი
    (C)
    decreasing the temperature and increasing the pressure
  • 30
    The oxidation of ammonia in excess air produces?
    პასუხი
    (A)
    NO
  • 31
    Hydrogen sulphide gas can act as?
    პასუხი
    (D)
    a precipitating agent
  • 32
    The gasification of coke is used for the manufacturing of?
    პასუხი
    (C)
    synthetic gas
  • 33
    The gas that is most useful in protecting humans against solar radiation is?
    პასუხი
    (B)
    ozone
  • 34
    Which of the following allotrope of carbon is a constituent of a lead pencil?
    პასუხი
    (A)
    Graphite
  • 35
    which of the following metals will show the highest metallic character?
    პასუხი
    (C)
    Barium
  • 36
    Copper metal dissolves in concentrated trioxonitrate (V) acid with the resultant evolution of?
    პასუხი
    (C)
    NO2
  • 37
    The type of iron that is best suited for welding, making nails, chains and iron rods is?
    პასუხი
    (B)
    wrought iron
  • 38
    In the electrolytic extraction of aluminum, the function of the molten cryolite is to
    პასუხი
    (B)
    lower the melting point of aluminium oxide
  • 39
    One of the products of the thermal decomposition of sodium trioxonitrate (V) is?
    პასუხი
    (C)
    sodium dioxonitrate (III)
  • 40
    A cracking process in petroleum refining can be represented by
    პასუხი
    (C)
    heptane to propene and butane
  • 41
    Which of the following molecules has two other positional isomers?
    პასუხი
    (D)
    CH2CHBrCH2Br
  • 42
    Which of the following class of compounds can exist as dipolar ions in solution?
    პასუხი
    (D)
    Amino acids
  • 43
    Lucas reagent is used to test for?
    პასუხი
    (C)
    alkanols
  • 44
    A compound commonly used for sterilization and preservation of specimens and food is
    პასუხი
    (A)
    ethanol
  • 45
    An organic compound reacted with bromine water to give a colourless solution. The compound is probably an?
    პასუხი
    (A)
    alkene