JAMB - Chemistry (2005)

  • 1
    Which of the following equimolar solutions will have the highest pH?
    Відповідь
    (B)
    NaOH
  • 2
    Which of the following ions require the largest quantity of electricity for discharge at an electrode?
    Відповідь
    (D)
    2.0 moles of Al3+
  • 3
    Phenolphthalein in acidic solution is
    Відповідь
    (C)
    colourless
  • 4
    When iron is exposed to moisture and it rusts, the value of ΔG for the reaction is
    Відповідь
    (D)
    negative
  • 5
    In which of the following reactions can the oxidation number of the nitrogen be said to have increased?
    Відповідь
    (A)
    2NO(g) + O2(g) → 2NO2(g)
  • 6
    2H\(_2\) + O\(_2\) → 2H\(_2\)O  ΔH = - 571kJ
    In the equation above, how much heat will be liberated if 12.0g of hydrogen is burnt in excess oxygen?
    Відповідь
    (D)
    -1713 kJ
  • 7
    A concentrated solution containing H\(^+\), Cu\(^{2+}\), OH\(^-\) and Cl\(^-\) was electrolyzed using platinum electrodes.
    The ion that will be discharged at the cathode is?
    Відповідь
    (A)
    Cu2+
  • 8
    When sulphur (IV) oxide is passed into a solution of sodium hydroxide for a long time, it eventually produces a solution of
    Відповідь
    (B)
    Na2SO3
  • 9
    What is the correct IUPAC name for NO\(_{2} ^{-}\)?
    Відповідь
    (D)
    Dioxonitrate (III) ion
  • 10
    What will happen if an aluminium spoon is used to stir a solution of iron (II) trioxonitrates (V)?
    Відповідь
    (A)
    The spoon will be oxidized while the iron (II) ions will be reduced to the metal
  • 11
    The enzymes responsible for converting sucrose into two simple isomeric sugars is
    Відповідь
    (C)
    invertase
  • 12
    The decolourization of purple colour of tetraoxomanganate (VII) ion is a test for
    Відповідь
    (A)
    alkenes
  • 13
    Which of the following are structural isomers?
    Відповідь
    (B)
    Propanal and propanone
  • 14
    In the purification of impure samples of ethyl ethanoate synthesized by esterification, concentrated sodium trioxocarbonate (IV) solution is used to remove
    Відповідь
    (C)
    acidic impurities
  • 15
    How many hydrogen atoms does a single ring cycloalkane have less than the corresponding open-chain alkane?
    Відповідь
    (A)
    Two
  • 16
    Equal moles of ethyne and hydrogen iodide react to give
    Відповідь
    (D)
    CH2 = CHI
  • 17
    A substance that is used as a ripening agent for fruits is
    Відповідь
    (A)
    ethene
  • 18
    When water boilers are used for long period of time, the solid substances left behind as scale are
    Відповідь
    (A)
    magnesium trioxosilicate (IV) and rust
  • 19
    25cm\(^3\) of a mixture of noble gases was obtained from air after the removal of other constituents. What was the original volume of air?
    Відповідь
    (A)
    2,500 cm3
  • 20
    The solubility curve shows the variation of solute concentration with
    Відповідь
    (B)
    temperature
  • 21
    The air around smelting industries is likely to contain
    Відповідь
    (C)
    H2, SO2 and CO2
  • 22
    Kerosene is commonly used to remove the red colour stain of palm oil from cloths because it
    Відповідь
    (C)
    makes the oil evaporate easily by dissolving it
  • 23
    The gas that is the most dangerous pollutant to human is
    Відповідь
    (D)
    hydrogen sulphide
  • 24
    Natural water collected from rivers and ponds contain oxygen, carbon (IV) oxide and
    Відповідь
    (A)
    nitrogen
  • 25
    How many moles of limestone will be required to produce 5.6g of CaO?
    [Ca = 40, C = 12, O= 16]
    Відповідь
    (B)
    0.10 mol
  • 26
    The shape of the hydrocarbon compound CH\(_4\) is
    Відповідь
    (D)
    tetrahedral
  • 27
    Which of these properties gives a solid its definite shape?
    Відповідь
    (A)
    strong intermolecular attraction
  • 28
    Sugar is separated from its impurities by
    Відповідь
    (B)
    crystallization
  • 29
    The component of an atom that contributes least to its mass is the
    Відповідь
    (D)
    electron
  • 30
    An element will readily form an electrovalent compound if its electron configuration is
    Відповідь
    (A)
    2, 8, 1
  • 31
    A heterogenous mixture can be defined as any mixture
    Відповідь
    (C)
    whose composition is not uniform
  • 32
    The pressure of 100cm\(^3\) of oxygen at 35\(^0\)C is 750mmHg. What will be the volume of gas if the pressure is reduced to 100mmHg without changing the temperature?
    Відповідь
    (D)
    750 cm3
  • 33
    I. Treatment of cancer
    II. Detection of leakages in water mains
    III. Detection of the ages of ancient tools
    IV. Preparation of drugs
    Which combination of the above refers to the uses of radioactive isotopes?
    Відповідь
    (D)
    I, II, III and IV
  • 34
    What is the valence shell electron configuration of the element with atomic number 17?
    Відповідь
    (D)
    3s2 3p5
  • 35
    The density of a certain gas is 1.98gdm\(^{-3}\) at s.t.p. What is the molecular mass of the gas?
    Відповідь
    (A)
    44.0 g
  • 36
    When pure aluminium metal is heated to red hot in the presence of nitrogen gas, the compound formed is
    Відповідь
    (C)
    AlN
  • 37
    A dense white fume is formed when ammonia gas reacts with
    Відповідь
    (D)
    HCl(g)
  • 38
    N\(_2\)(g) + 3H\(_2\)(g) ↔ 2NH\(_3\)(g) ΔH = - 90 kJ
    In the equation above, the yield of ammonia can be decreased by
    Відповідь
    (C)
    increase the temperature
  • 39
    The gas that can be dried using concentrated tetraoxosulphate (VI) acid is
    Відповідь
    (B)
    Sulphur (IV) oxide
  • 40
    NH\(_4\)Cl(s) ⇌ NH\(_3\)(g) + HCl(g)
    The reaction above can only attain equilibrium if
    Відповідь
    (C)
    it is in a closed system
  • 41
    The most suitable metal that can be used as lightning conductor is?
    Відповідь
    (B)
    copper
  • 42

    In the diagram above which of the curves illustrates Arrhenius' law?

    Відповідь
    (D)
    X
  • 43
    The most abundant element on the earth's crust is
    Відповідь
    (C)
    oxygen
  • 44
    Metalloids are also referred to as
    Відповідь
    (A)
    semi-metals
  • 45
    The ores that can be concentrated by flotation are
    Відповідь
    (B)
    sulphide ores