JAMB - Chemistry (2017)

  • 1
    The general formula of alkanones is
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    (B)
    RCOR'
  • 2
    The constituent common to duralumin and alnico is
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    (C)
    Al
  • 3
    The shape of the S-orbital is
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    (D)
    spherical
  • 4
    Aluminium hydroxide is used in the dyeing industry as a
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    (D)
    mordant
  • 5
    The tincture of iodine means iodine dissolved in
    отговор
    (A)
    ethanol
  • 6
    Temporary hard water is formed when rain water containing dissolved carbon(IV) oxide flows over deposits of
    отговор
    (A)
    CaCO3
  • 7
    The acid anhydride that will produce weak acid in water is
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    (D)
    CO2
  • 8
    The process that occurs when two equivalent forms of a compound are in equilibrium is
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    (B)
    Resonance
  • 9
    In the laboratory preparation of ethyl ethanoate, the water present in the mixture is removed using ?
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    (A)
    Anhydrous CaCl2
  • 10
    The constituent of air necessary in the rusting process are
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    (A)
    O2 and H2O
  • 11
    For a general equation of the nature xP + yQ → mR + nS, the expression for the equilibrium constant is
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    (C)
    \(\frac{[R]^m [S]^n}{[P]^x [Q]^y}\)
  • 12
    A given mass of gas occupies 2dm3 at 300k. At what temperature will its volume be doubled, keeping the pressure constant?
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    (D)
    600k
  • 13
    The oxidation number of iodine in KIO3 is
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    (C)
    +5
  • 14
    An isomer of C5H12 is
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    (C)
    2–methyl butane
  • 15
    When few drops of concentrated trioxonitrate(V) acid is added to an unknown sample and wanned an intense yellow colouration is observed. The likely functional group present in the sample is
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    (A)
    NH2RCHCOOH
  • 16
    A sample of orange juice is found to have a PH of 3.80. What is the concentration of the hydroxide ion in the juice?
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    (B)
    6.3 \(\times\) 10-11
  • 17
    Incomplete oxidation of ethanol yields
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    (D)
    CH3CHO
  • 18
    The salt formed from a weak acid and a strong base hydrolyzes in water to form
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    (D)
    an alkaline solution
  • 19
    The ideal gas laws and equations are true for all gases at
    отговор
    (D)
    low pressure and high temperatures
  • 20
    When ΔH is negative, a reaction is said to be
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    (B)
    exothermic
  • 21
    \(^{226}_{88}Ra\) → \(^x_{86}Rn\) + alpha particle
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    (D)
    222
  • 22
    The shape of ammonia molecules is
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    (A)
    trigonal pyramidal
  • 23
    The mass of silver deposited when a current of 10A is passed through a solution of silver salt for 4830s is – (Ag = 108 F = 96500(mol-1)
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    (A)
    54.0g
  • 24
    Tin is unaffected by air at ordinary temperature due to its?
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    (B)
    Weak electropositive character
  • 25
    Calculate the amount in moles of silver deposited when 9650C of electricty is passed through a solution of silver salt [= 96500 Cmol-1]
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    (D)
    0.10
  • 26
    The reaction of halogens with alkanes in the presence of sunlight is an example of
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    (D)
    substitution reaction
  • 27
    The enzyme used in the hydrolysis of starch to dextrin and maltose is?
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    (B)
    amylase
  • 28
    The alkyl group is represented by the general formula
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    (C)
    CnH2n + 1
  • 29
    Cu\(_2\)S(g) + O\(_2\)(g) → 2Cu + SO\(_2\)(g)
    What is the change in the oxidation number of copper in the reaction?
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    (C)
    + 1 to 0
  • 30

    In the diagram above. X is

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    (B)
    SO2
  • 31

    The diagram above. Y is

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    (D)
    Concentrated H2SO4
  • 32
    Calculate the mass of copper deposited when a current of 0.5 ampere was passed through a solution of copper(II) chloride for 45 minutes in an electrolytic cell. [Cu = 64, F = 96500Cmol-1]
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    (D)
    0.448g
  • 33


    The IUPAC nomenclature of the structure above is

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    (B)
    2-methylbut-1-ene
  • 34
    The reddish–brown rust on iron roofing sheets consists of
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    (C)
    Fe2O3.XH2O
  • 35
    The densities of two gases, X and Y are 0.5gdm-3 and 2.0gdm-3 respectively. What is the rate of diffusion of X relative to Y?
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    (C)
    2.0
  • 36
    The carbon atoms on ethane are
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    (B)
    sp3 hybridized
  • 37
    According to Charle's law, the volume of a gas becomes zero at
    отговор
    (B)
    −273°c
  • 38
    An oxide XO2 has a vapour density of 32. What is the atomic mass of X?
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    (B)
    32
  • 39
    The gas that can be collected by downward displacement of air is
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    (D)
    ammonia
  • 40
    In the laboratory preparation of trioxonitrate (V) acid the nitrogen(iv) oxide formed as a by-product is removed by
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    (D)
    bubbling air through the acid solution
  • 41
    A particle that contains 9 protons, 10 neutrons and 10 electrons is
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    (D)
    negative ion
  • 42
    Ethene is prepared industrially by
    отговор
    (D)
    Cracking
  • 43
    Calculate the amount in moles of a gas which occupies 10.5 dm3 at 6 atm and 30oC [R = 0.082 atm dm3 K-1 mol-1]
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    (A)
    2.536
  • 44
    If 100cm3 of oxygen pass through a porous plug is 50 seconds, the time taken for the same volume of hydrogen to pass through the same porous plug is? [O = 16, H = 1]
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    (B)
    12.5s
  • 45
    Due to the high reactivity of sodium, it is usually stored under
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    (C)
    paraffin