WAEC - Chemistry (2017)

  • 1
    Which of the following species determines the chemical properties of an atom?
    Atbilde
    (A)
    Electron
  • 2
    The following glasswares are used to measure the volume of liquids EXCEPT
    Atbilde
    (C)
    test tube
  • 3
    Pauli exclusion principle is related to
    Atbilde
    (D)
    quantum numbers of electrons
  • 4
    The species with no electron in the 3d-orbital is
    Atbilde
    (B)
    \(Sc^{3+}\)
  • 5
    The seperation of Nitrogen from oxygen using fractional distillation of air is possible because
    Atbilde
    (C)
    of the difference in their boiling points
  • 6
    The purity of a solid sample can best be determined by its
    Atbilde
    (B)
    melting point
  • 7
    The mass of one mole of \((NH_{4})_{2}CO_{3}\) is   [O=16.0, N=14.0, C=12.0, H=1.0]
    Atbilde
    (D)
    96.0g
  • 8
    Atomic orbital is
    Atbilde
    (B)
    a region around the nucleus where electrons are most likely to be found
  • 9
    The property of elements which increases down a group of the periodic table is
    Atbilde
    (C)
    ionic radius
  • 10
    The reason for the decrease in the atomic size of elements across a period is that
    Atbilde
    (A)
    nuclear charge increases while the outermost electrons are drawn closer to the nucleus
  • 11
    The oxidation number of nitrogen in \(Pb(NO_{3})_{2}\) is
    Atbilde
    (D)
    +5
  • 12
    Which of the following arrangements indicates the correct decreasing order of ionization energy of period 3 elements?
    Atbilde
    (B)
    Cl, P, Al, Na
  • 13
    Which of the following metals has the strongest metallic bond?
    Atbilde
    (A)
    \(_{13}Al\)
  • 14
    Which of the following substances does not have van der Waals' forces?
    Atbilde
    (A)
    Copper
  • 15
    The oxidation number of X in \(XO_{4}^{3-}\) is
    Atbilde
    (D)
    +5
  • 16
    The ionization energy is affected by the following factors except
    Atbilde
    (C)
    ability to attract shared electron(s)
  • 17
    Which of the following statements is correct?
    Atbilde
    (D)
    Ionic compounds in solution would conduct electricity
  • 18
    The bond angle in tetrahedral molecules such as tetrachloromethane is 
    Atbilde
    (B)
    109.5°
  • 19
    The properties of a good primary standard include the following except
    Atbilde
    (B)
    low molecular mass
  • 20
    The use of diamond in abrasives is due to its
    Atbilde
    (B)
    hardness
  • 21
    Which of the following statements about endothermic reaction is correct?
    Atbilde
    (D)
    Heat energy is absorbed
  • 22
    A 0.1\(moldm^{-3}\) solution of sodium hydroxide was diluted with distilled water to 0.001\(moldm^{-3}\). What is the dilution factor?
    Atbilde
    (B)
    100.00
  • 23
    Graphite and Diamond are similar in that they
    Atbilde
    (C)
    form carbon(IV) oxide on combustion
  • 24
    In a saturated solution at a given temperature, the undissolved solutes are in equilibrium with
    Atbilde
    (B)
    dissolved solute particles
  • 25
    The number of atoms present in 2.5moles of a triatomic gas is equivalent to [1mole = \(6.02\times 10^{23}\)]
    Atbilde
    (C)
    \(1.5\times 10^{24}\)
  • 26
    When Magnesium reacts with oxygen, heat is 
    Atbilde
    (C)
    evolved and the reaction is exothermic
  • 27
    Which of the following gases is not acidic?
    Atbilde
    (D)
    CO
  • 28
    A hydrocarbon contained 14.3% hydrogen. The empirical formula for the hydrocarbon is   [H= 1.0, C= 12.0]
    Atbilde
    (B)
    \(CH_{2}\)
  • 29
    Which of the following statements is NOT a chemical property of an acid?
    Atbilde
    (A)
    Evolution of ammonia when heated with ammonium salts
  • 30
    Halogens generally react with metals to form
    Atbilde
    (D)
    salts
  • 31
    Potassium Chloride solid does not conduct electricity because
    Atbilde
    (B)
    strong cohesive forces make its ions immobile
  • 32
    When water was added to a white anhydrous substance X, the colour changed to blue. X is
    Atbilde
    (A)
    \(CuSO_{4}\)
  • 33
    Solubility curve can be used in the determination of the
    Atbilde
    (C)
    amount of solid drugs in a given solution
  • 34
    If 0.2g of a salt is required to saturate 200\(cm^{3}\) of water at room temperature, what is the solubility of the salt?
    Atbilde
    (B)
    1.0\(gdm^{-3}\)
  • 35
    The property of a chemical reaction that is affected by the presence of a catalyst is
    Atbilde
    (A)
    activation energy
  • 36
    Soluble salts can be prepared by the following methods except
    Atbilde
    (C)
    double decomposition
  • 37
    Chemical reactions occurs when the colliding reactants have energy that is
    Atbilde
    (B)
    greater than the activation energy
  • 38
    The common feature of reactions at the anode is that
    Atbilde
    (C)
    oxidation is involved
  • 39
    Consider the following reaction equation: \(2NO_{(g)} + O_{{2}{(g)}} \to 2NO_{{2}{(g)}}\). What is the change in the oxidation number of nitrogen?
    Atbilde
    (C)
    +2 to +4
  • 40
    Which of the following factors characterize members of the same homologous series?
    Atbilde
    (D)
    Successive members undergo changes in molecular formula by \(CH_{2}\)
  • 41
    Calculate the mass of copper deposited if a current of 0.45A flows through \(CuSO_{4}\) solution for 1hour 15mins.   [Cu=64.0, S= 32.0, O =16.0, 1F= 96500C]
    Atbilde
    (B)
    0.67g
  • 42
    Classification of alkanols is based on the 
    Atbilde
    (D)
    number of alkyl groups bonded to the carbon having the hydroxyl group
  • 43
    The name of the compound \(C_{4}H_{9}COOC_{3}H_{7}\) is
    Atbilde
    (A)
    propyl pentanoate
  • 44
    Which of the following pairs of gases are pollutants from car exhaust?
    Atbilde
    (C)
    Carbon(II) oxide and Sulphur(IV) oxide
  • 45
    Fats and oils can be obtained from any of the following sources except
    Atbilde
    (A)
    paraffin oil