JAMB - Chemistry (1988)

  • 1
    Which of the following statements is NOT correct?
    პასუხი
    (B)
    At constant temperature, the volume of a gas increases as the pressure increases
  • 2
    The ion that may be assumed to have negligible concentration in a sample of water that lathers readily with soap is?
    პასუხი
    (A)
    Mg+
  • 3
    A substance S is isomorphous with another substance R. When a tiny crystals of S is added into a supersaturated solution of R?
    პასუხი
    (B)
    crystals of R are precipitated
  • 4
    Which of the following dilute solutions has the lowest pH value?
    პასუხი
    (C)
    Hydrochloric acid
  • 5
    Which of the following in aqueous solution is neutral to litmus?
    პასუხი
    (D)
    NaCl
  • 6
    What volume of a 0.1 M H\(_3\)PO\(_4\) will be required to neutralize 45.0 cm\(^3\) of a 0.2 M NaOH?
    პასუხი
    (D)
    30.0 cm3
  • 7
    Which of the following substances is a basic salt?
    პასუხი
    (B)
    Mg(OH)CI
  • 8
    Which of the following acts both s a reducing and an oxidizing agent?
    პასუხი
    (B)
    SO2
  • 9
    Which of the following reactions takes place in the cathode compartment during the electrolysis of copper (II) chloride solution?
    პასუხი
    (A)
    Cu2+ + 2e- → Cu(s)
  • 10
    A mixture of starch solution and potassium iodide was placed in a test tube. On adding dilute tetraoxosulphate (lV) acid and then K2Cr2O7 solutions, a blue-black colour was produced. In this reaction, the?
    პასუხი
    (C)
    starch has been oxidized
  • 11
    Which of the following will produce the greatest increase in the rate of the chemical reaction represented by the equation Na2S2O3(aq) + 2HCl(aq) → 2NaCI(aq) + H2O(I) + SO2(g) + S(g)?
    პასუხი
    (C)
    An increase in temperature and an increase in the concentration of the reactants
  • 12
    Which of the followingstatements is TRUE?
    პასუხი
    (D)
    The heat of solution of NaOH(s) is negative
  • 13
    Which property of a reversible reaction is affected by a catalyst?
    პასუხი
    (B)
    Energy of activation
  • 14
    Which of the following is used in fire extinguishers?
    პასუხი
    (B)
    Carbon (lV) oxide
  • 15
    When H2S gas is passed into a solution of iron (III) chloride, the colour changes from yellow to green. This is because?
    პასუხი
    (D)
    Fe3+ ions are reduced to Fe2+ ions
  • 16
    Suitable reagents for the laboratory preparation nitrogen are?
    პასუხი
    (A)
    sodium dioxonitrate (III) and ammonium chloride
  • 17
    The thermal decomposition of copper (ll)trioxonitrate (V) yields copper (ll) oxide, oxygen and?
    პასუხი
    (C)
    nitrogen (lV) oxide
  • 18
    Chlorine is produced commmercially by?
    პასუხი
    (B)
    electrolysis of brine
  • 19
    Aluminium is extracted commercially from its ore by?
    პასუხი
    (B)
    the electrolysis of fused aluminium oxide in cryolite
  • 20
    Given the reactions (i) Fe(s) + X(NO3)2(aq) → Fe(NO3) + X(s) (ii) H2(g) + XO → X + H2O(s); X is likely to be?
    პასუხი
    (A)
    copper
  • 21
    Crude copper can be purified by the electrolysis of CuSO4(aq) if?
    პასუხი
    (B)
    the crude copper is made the anode of the cell
  • 22
    Methylethanoate reacts with ammonia to yield?
    პასუხი
    (D)
    ethanamide and methanol
  • 23
    Alkanoates are formed by the reaction of alkanoic acid with?
    პასუხი
    (B)
    alkanols
  • 24
    The four classes of hydrocarbons are?
    პასუხი
    (B)
    alkanes, alkenes, alkynes and aromatics
  • 25
    Which of the following compounds has the highest boiling point?
    პასუხი
    (A)
    CH3CH2CH2CH2HO
  • 26
    Detergents have the general formula?
    პასუხი
    (B)
    RSO3-Na+
  • 27
    What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?
    პასუხი
    (B)
    Destructive distillation
  • 28
    The formula of a compound formed in a reaction between a trivalent metal M and a tetravalent non-metal X is~?
    პასუხი
    (C)
    M4X3
  • 29
    2.25g of a sample of an oxide of copper on reduction gave 2.0g of copper. 2.50g of another oxide of copper on reduction also gave 2.0g of copper. These results are in accordance with the law of?
    პასუხი
    (C)
    multiple proportions
  • 30
    One mole of propane is mixed with five moles of oxygen. The mixture is ignited and the propane burns completely. What is the volume of the products at s.t.p?

    (G.M.V = 22.4 dm3 mol-1)
    პასუხი
    (B)
    67.2 dm3
  • 31
    An increase in temperature causes an increase in the pressure of a gas because there is an increase in the?
    პასუხი
    (B)
    number of collisions between the molecules
  • 32
    The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as?
    პასუხი
    (D)
    Van der waals
  • 33
    A metallic ion X2+ with an inert gas structure contains 18 electrons. How many protons are there in this ion?
    პასუხი
    (A)
    20
  • 34
    Which of the following physical properties decreases across the Periodic Table?
    პასუხი
    (D)
    Atomic radius
  • 35
    What are the possible oxidation numbers of an element if its atomic number is 17?
    პასუხი
    (A)
    -1 and 7
  • 36
    The energy changes accompanying the addition of an electron to a gaseous atom is called?
    პასუხი
    (C)
    electron affinity
  • 37
    The molar ratio of oxygen to nitrogen in dissolved air is 2:1 whereas the ratio is 4:1 in atmospheric air because?
    პასუხი
    (A)
    nitrogen is less soluble than oxygen
  • 38
    An eruption pollution an environment with gas suspected to be H2S, a poisonous gas. A residue team should spray the environment with?
    პასუხი
    (B)
    moist SO2
  • 39
    In the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of
    პასუხი
    (C)
    sublimation
  • 40
    Which of the gas laws does the above graph illustrate?
    პასუხი
    (B)
    Charles