JAMB - Chemistry (1999)

  • 1
    200cm\(^3\) each of 0.1M solutions of lead (II) trioxonitrate(V) and hydrochloric acid were mixed. Assuming that lead (II) chloride is completely insoluble, calculate the mass of lead (II) chloride that will be precipitated.
    [Pb = 207, Cl= 35.5, N = 14, O = 16]
    Хариулт
    (A)
    2.78g
  • 2
    56.00cm3 of a gas at S.T.P. weighed 0.11g. What is the vapour density of the gas?
    [Molar volume of a gas at S.T.P = 22.4dm3]
    Хариулт
    (B)
    22.00
  • 3
    Which of the following gases will diffuse fastest when passed through a porous plug?
    [H = 1, C = 12, N = 14, O = 16]
    Хариулт
    (C)
    Methane
  • 4
    Which is the temperature of a given mass of a gas initially at 0°C and 9 atm, if the pressure is reduced to 3 atm at constant volume?
    Хариулт
    (A)
    91K
  • 5
    Which of the following will have its mass increased when heated in air?
    Хариулт
    (B)
    Magnesium
  • 6
    Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
    From the equation above, the mass of magnesium required to react with 250cm3 of 0.5M HCl is
    [Mg = 24]
    Хариулт
    (B)
    1.5g
  • 7
    A gaseous metallic chloride MClx consists of 20.22% of M by mass. The formula of the chloride is?
    [M = 27, Cl = 35.5]
    Хариулт
    (C)
    MCl3
  • 8
    In which of the following are water molecules in the most disorderly arrangement?
    Хариулт
    (D)
    Steam at 100°C
  • 9
    In order to remove one electron from a 3S orbital of gaseous sodium atom, about 496KJMol-1 of energy is required. This energy is referred to as
    Хариулт
    (B)
    ionization energy
  • 10
    Nitrogen obtained from the liquefaction of air has a higher density than that obtained from nitrogen containing compounds because the former contains
    Хариулт
    (D)
    rare gases
  • 11
    The method that can be used to convert hard water to soft water is
    Хариулт
    (C)
    the use of an ion-exchange resin
  • 12
    1s2, 2s2, 2p6, 3s2, 3p6, 3d7, 4s2
    An element with the electronic configuration above is a
    Хариулт
    (C)
    transition element
  • 13
    Given that electronegativity increases across a period and decreases down a group in the periodic table, in which of the following compounds will the molecules be held together by the strongest hydrogen bond?
    Хариулт
    (A)
    HF(g)
  • 14
    0.25 mole of hydrogen chloride was dissolved in distilled water and the volume made up of 0.50 dm3. If 15.0 cm3 of the solution requires 12.50 cm3 of aqueous sodium trioxocarbonate (IV) for neutralization, calculate the concentration of the alkaline solution
    Хариулт
    (A)
    0.30 mol dm3
  • 15
    The correct order of increasing oxidation number of the transition metal ions for the compounds K2Cr2O7, V2O5 and KMnO4 is
    Хариулт
    (A)
    V2O5 < K2Cr2O7 < KMnO4
  • 16
    The set of pollutants that is most likely to be produced when petrol is accidentally spilled on plastic materials and ignited is
    Хариулт
    (B)
    CO, HCL and SO2
  • 17
    What is observed when aqueous solutions of each of tetraoxosulphate (VI) acid, potassium trioxoiodate (V) and potassium iodide are mixed together?
    Хариулт
    (D)
    The mixture turns reddish brown
  • 18
    The solution with the lowest pH value is 
    Хариулт
    (C)
    15 ml of (m/5) HCl
  • 19
    The solubility product of Cu(IO3)2 is 1.08 * 10-7. Assuming that neither ions react appreciable with water to form H+ and OH-, what is the solubility of this salt?
    Хариулт
    (C)
    3.0 * 10-3 mol dm-3
  • 20
    The entropy and enthalpy of a system are a measure of
    Хариулт
    (A)
    degree of disorderlinesss and heat content respectively
  • 21
    2SO2(g) + O2(g) ↔ 2SO3(g). In the chemical reaction above, the substance that will increase the rate of production of sulphur (VI) oxide is
    Хариулт
    (C)
    vanadium (V) oxide
  • 22
    N\(_2\)O\(_4\)(g) ↔ 2NO\(_2\)(g). Increase in total pressure of the equilibrium reaction above will
    Хариулт
    (D)
    produce more of N2O4(g) in the mixture
  • 23
    What quantity of electricity will liberate 0.125 mole of oxygen molecules during the electrolysis of dilute sodium chloride solution?
    [ F = 96 5000 C mol-1 ]
    Хариулт
    (B)
    48 250 coulombs
  • 24
    X + Y → Z. The rate equation for the chemical reaction above is \(\frac{-Δx}{Δt}\) = K[X]\(^2\)[Y].
    The overall order of the reaction is?
    Хариулт
    (D)
    3.0
  • 25
    When a current I was passed through an electrolyte solution for 40 minutes, a mass X g of a univalent metal was deposited at the cathode. What mass of the metal will be deposited when a current 2I is passed through the solution for 10 minutes?
    Хариулт
    (B)
    X/2 g
  • 26
    RS(aq) + HF(aq) → RF(s) + HS(aq)
    ΔH = -65.7 kj mol(-1).
    From the equation above, it can be deduced that
    Хариулт
    (B)
    the heat content of the reactants is higher than that of the products
  • 27
    Which of the following statement is true of the electrochemical series?
    Хариулт
    (D)
    Electropositivity of metals decreases down the series
  • 28
    The gas that will form a white precipitate with acidified silver trioxonitrate (v) is
    Хариулт
    (D)
    HCL
  • 29
    Chlorine, bromine and iodine resemble one another in that they?
    Хариулт
    (A)
    dissolve in alkalis
  • 30
    The salt that reacts with dilute hydrochloric acid to produce a pungent smelling gas which decolourizes acidified purple potassium tetraoxomanganate (VII) solution is
    Хариулт
    (B)
    Na2SO3
  • 31
    A pair of compounds that can be used to generate a gas which has physiological effect on human beings is
    Хариулт
    (C)
    sodium trioxonitrate (V) and ammonium chloride
  • 32
    Hydrogen is used in oxy-hydrogen flames for melting metals because it
    Хариулт
    (A)
    evolves a lot of heat when burnt
  • 33
    What properties of duralumin make it more useful than its constituent metals?
    Хариулт
    (C)
    It is strong and light
  • 34
    The pair of metals in the reactivity series that are usually extracted by the electrolysis of their ores is
    Хариулт
    (B)
    magnesium and calcium
  • 35
    A metal that can be extracted from cassitertite is
    Хариулт
    (C)
    tin
  • 36
    Which of the following metals is passive to concentrated trioxonitrate (V) acid?
    Хариулт
    (A)
    Iron
  • 37
    The hydrocarbon that burns in air with a sooty flames is
    Хариулт
    (D)
    C6H6
  • 38
    2-methylprop-1-ene is an isomer of
    Хариулт
    (A)
    but-2-ene
  • 39
    Which of the following is a solvent for perfumes?
    Хариулт
    (D)
    C2H5OH
  • 40
    When excess ethanol is heated to 145oC in the presence of concentrated H2SO4, the product is
    Хариулт
    (C)
    diethyl ether
  • 41
    POlyvinyl chloride is used to produce
    Хариулт
    (D)
    pipes
  • 42
    An organic compound that does not undergo a reaction with both hydrogen cyanide and hydroxylamine can be
    Хариулт
    (A)
    alkene
  • 43
    When the two end alkyl groups ethyl ethanoate are interchange, the compound formed is known as
    Хариулт
    (C)
    methyl propanoate
  • 44
    From the diagram above the mass of crystals deposited when 1 dm 3 of a saturated solution of NaCl is cooled from 80 oC to 60oC is
    [Na = 23, Cl = 35.5]
    Хариулт
    (A)
    117.00 g
  • 45
    In the diagram above, Y is a mixture of
    Хариулт
    (A)
    calcium hydroxide and ammonium chloride