WAEC - Chemistry (2011)

  • 1
    How many isotopes has hydrogen?
    Jibu
    (B)
    3
  • 2
    Which of the following electrons configurations correctly represents an inert element?
    Jibu
    (D)
    1s22s22p6
  • 3
    What type of reaction is represented by the following equation?\(\frac{2}{1}\)D\(\frac{3}{1}\)H → \(\frac{4}{4}\)He + \(\frac{1}{0}\)n + energy
    Jibu
    (B)
    Nuclar fusion
  • 4
    Which of the following ions has the electron configuration 2,8,8?
    Jibu
    (D)
    CI-
  • 5
    An element with the electron configuration of 1s 22s 22p 6 would have a combining power of
    Jibu
    (A)
    o
  • 6
    Rare gases are stable because they
    Jibu
    (D)
    have octet structure
  • 7
    Which of the following elements would produce coloured ions in aqueous solution?
    Jibu
    (B)
    lron
  • 8
    The energy change that accompanies the addition of an electron to an isolated gaseous atom is
    Jibu
    (C)
    electron affinity
  • 9
    Which of the following hydrohalic acids is the weakest?
    Jibu
    (D)
    HI
  • 10
    Which of the following arrangements is in order of increasing metallic property?
    Jibu
    (A)
    Li < Na< k
  • 11
    Chlorine, bromine and iodine belong to the same group and
    Jibu
    (D)
    react with alkali
  • 12
    Which of the following elements can conveniently be placed in two groups in the periodic table ?
    Jibu
    (C)
    Hydrogen
  • 13
    The bond formed when two electrons that are shared between two atoms are donated by only one of the atoms is
    Jibu
    (B)
    dative
  • 14
    When element 20A combines with element 8Y,
    Jibu
    (B)
    an ionic compound AY is formed
  • 15
    In metallic colids, the forces of attraction are between the mobile valence electrons and
    Jibu
    (D)
    positively charged nuclei
  • 16
    Which of the following statements about displacement reaction is correct?
    Jibu
    (A)
    A more electropositive element displaces a less electroposive one
  • 17
    The volume occupied by 17g of H2S at s.t.p. is [H = 1.00, S = 32.0, Molar volume = 22.4 dm3]
    Jibu
    (A)
    11.2dm 3
  • 18
    Consider the reaction represented by the following equation: xKMnO 4(aq) + ySO2(g) + zH2O(I) → K 2SO4(AQ) + 2MnSO4(aq) + 2H2SO x,y and z are respectively
    Jibu
    (A)
    2,5 and 2
  • 19
    What is the amount of magnesium that would contain 1.20 x 1024 particles? [Mg = 24, Avogadro's constant = 6.02 x 1023]
    Jibu
    (B)
    2.0 moles
  • 20
    The number of atoms in one mole of a substance is equal to the
    Jibu
    (D)
    avogadro number
  • 21
    Which of the following statements about a molar solution is correct? it
    Jibu
    (D)
    contains one mole of the solute in 1 dm3 of solution
  • 22
    A gas that is collected by upward delivery is likely to be
    Jibu
    (C)
    lighter than air
  • 23
    Bubbling excess carbon (IV) oxide into calcium hydroxide solution results in the formaton of
    Jibu
    (B)
    Ca(HCO3)2
  • 24
    The equation P = \(\frac{K}{V}\) illustrates
    Jibu
    (A)
    Boyle's law
  • 25
    The initial volume of a gas at 300 K was 220 cm 3 Determine its temperature if the volume became 250 cm 3
    Jibu
    (D)
    341 K
  • 26
    Which of the following equimolar solutions has the highest conductivity?
    Jibu
    (C)
    H 2SO 4(aq)
  • 27
    The colour of phenolphthalein indicator in alkaline solution at the end-point of an acid-base titration is?
    Jibu
    (C)
    pink
  • 28
    Which of the following statements about enthalpy of neutralization is correct? It
    Jibu
    (A)
    is constant for a strong acid and a strong base
  • 29
    When NH 4CI was dissolved in water, the container was cold to touch. This implies that
    Jibu
    (A)
    the process is endothermic
  • 30
    Which of the following metallic oxides is amphoteric?
    Jibu
    (A)
    AI2O3
  • 31
    On evaporation to dryness, 250 cm3 of saturated solution of salt X with relative molar mass 101 gave 50.5g of the. What is the soluility of the salt?
    Jibu
    (B)
    2.0 mol dm-3
  • 32

    Consider the following reaction equation:

    X(g) + Y(g) ⇌ XY(g); ∆H = + 220KJ mol-1 If the temperature of the system is increased, the

    Jibu
    (B)
    forward reaction would favoured
  • 33
    What is the value of n in the following equation? Cr2O72- + 14H+ + ne- → 2Cr 3+ + 7H2O
    Jibu
    (C)
    6
  • 34
    What mass of copper would be formed when a current of 10.0 A is passed through a solution of CuSO4 for 1 hour? [Cu = 63.5; 1F = 96500C]
    Jibu
    (B)
    11.8 g
  • 35
    Which of the following metals could be used as sacrifical anode for preventing the corrosion of iron?
    Jibu
    (C)
    Magnesium
  • 36
    Consider the following electrochemical cell notation: M(s) / M2+ (aq)// H+ (aq)/ H2(g). The value of the electrode potential is positive when?
    Jibu
    (B)
    electrons fow from hydrogen electrode, H2(g) to metal electrode, M(s)
  • 37
    Which of the following compounds determines the octane rating of petrol?
    Jibu
    (D)
    2,2,4 - trimethylpentane
  • 38
    Which of the following compounds would react with ethanoic acid to give a sweet smelling liquid?
    Jibu
    (B)
    Alkanol
  • 39
    Which of the following separation techniques would show that black ink is a mixture of chemical compounds?
    Jibu
    (B)
    Chromatography
  • 40
    The following substances are examples of addition polymer except
    Jibu
    (A)
    nylon
  • 41
    When bromine is added to ethene at room temperature, the compound formed is
    Jibu
    (D)
    1,2 - dibromoethane
  • 42
    The compound that makes palm wine taste sour after exposure to the air for few days is
    Jibu
    (A)
    ethanol
  • 43
    The reagent that can be used to distinguish ethene from ethyne is
    Jibu
    (A)
    ammoniacal silver trioxonitrate (V) solution
  • 44
    The following substances are ores of metals except
    Jibu
    (D)
    graphite
  • 45
    Which of the following processes does not involve the use of limestone?
    Jibu
    (B)
    Manufacture of tetraoxosulphate (VI) acid by Contact process