Chemistry JAMB, WAEC, NECO AND NABTEB Official Past Questions

22

A basic postulate of the kinetic theory of gases is that the molecules of a gas move in straight lines between collisions. This implies that?

  • A. collisions are perfectly elastic
  • B. forces of repulsion exist
  • C. forces of repulsion are in equilibrium
  • D. collision are inelastic
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23

Equal volumes of CO,SO2, NO2 and H2S were released into a room at the same point and time. Which of the following gives the order of diffusion of the gases to the opposite corner of the room?
(S = 32, C = 12, O = 16, N = 14, H = 1)

  • A. CO, SO2,NO2,H2S
  • B. SO2,NO2,H2S,CO
  • C. CO,H2S,SO2,NO2
  • D. CO,H2S,NO2,SO2
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24

The volume occupies by 1.58g of a gas at s.t.p is 500cm3. What is the relative molecular mass of the gas?

(G.M.V at s.t.p = 22.40dm3)

  • A. 28
  • B. 32
  • C. 44
  • D. 71
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25

If a gas occupies a container of volume 146 cm3 at 18°C and 0.971 atm, its volume in cm3 at s.t.p is?

  • A. 133
  • B. 146
  • C. 266
  • D. 292
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26

Which of the following is formed when maltose reacts with concentrated tetraoxosulphate (VI) acid ?

  • A. Carbon (IV) oxide
  • B. Coal tar
  • C. Charcoal
  • D. Toxic fumes
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27

The octane number of a fuel whose performance is the same as that of a mixture of 55 g of 2,2,4- trimethly pentane and 45 g of n-heptane is ?

  • A. 45
  • B. 55
  • C. 80
  • D. 100
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28

Alkaonic acids have low volatility compared with alkanols because they?

  • A. are more polar than alkaonls
  • B. have two oxygen atoms while alkanols have one
  • C. form hydrogen bonds while alkanols do not
  • D. form two hydrogen bonds while alkanols form one
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29

The label on a reagent bottle containing a clear organic liquid dropped off.The liquid was neutral to litmus and gave a colourless gas with metallic sodium. The liquid must be an?

  • A. alkanoate
  • B. alkaene
  • C. alkanol
  • D. alkane
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30

A cycloalkane with the molecular formula C5H10 has ?

  • A. one isomer
  • B. two isomers
  • C. three isomers
  • D. four isomers
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31

Which of the following compounds gives a yellow residue when heated and also reacts with aqueous sodium hydroxide to give a white gelatinous precipitate soluble in excess sodium hydroxide solution?

  • A. (NH4)CO3
  • B. ZnCO3
  • C. Al2(SO4)3
  • D. PbCO3
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32

To make coloured glasses, small quantities of oxides of metals which form coloured silicates are often added to the reaction mixture consisting of Na2CO3 and SiO2. Such a metals is a?.

  • A. pottasium
  • B. barium
  • C. zinc
  • D. copper
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33

Sodium hydroxide should be stored in properly closed containers because it?

  • A. readily asborbs water vapour to air
  • B. is easily oxidize by atmospheric oxygen
  • C. turns golden yellow when exposed to light
  • D. melts at a low temperature
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34

The major component of the slag from the production of iron is?

  • A. an alloy of calcium and iron
  • B. coke
  • C. impure iron
  • D. calcium trioxosilicate (IV)
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35

Coal fire should not be used in poorly ventilated rooms because ?

  • A. of the accumulation of CO2 which causes dep sleep
  • B. it is usually too hot
  • C. of the acumulation of CO which causes suffocation
  • D. it removes most most of the gases in the rooms
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36

Which of the following metals will liberate hydrogen from steam or dilute acid?

  • A. Copper
  • B. Iron
  • C. Lead
  • D. Mercury
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37

A metallic oxide which reacts with both HCl and NaOH to give salt and water only can be classified as?

  • A. an acidic oxide
  • B. a basic oxide
  • C. a neutral oxide
  • D. an amphoteric oxide
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38

In the Haber process for the manufacture of ammonia, the catalyst commonly used is finely divided ?

  • A. vanadium
  • B. platinum
  • C. iron
  • D. copper
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39

Which of the following tests will completely identify anyone of surphur (VI) oxide, hydrogen, carbon (IV) oxide and nitrogen (II) oxide?

  • A. Pass each gas into water and test with blue litmus paper
  • B. Pass each gas into lime water
  • C. Expose each gas to atmospheric air
  • D. Pass each gas to concentrated tetraoxosulphate (IV) acid
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40

The brown fumes given off when trioxonitrate (V) acid is heated consist of ?

  • A. NO2 and O2
  • B. H2O and NO2
  • C. NO2' O2 and H2O
  • D. NO, NO2 and H2O
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41

Which of the following gases can be collected by the upward displacement of air?

  • A. NO
  • B. H 2
  • C. NH3
  • D. Cl 2
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42

In the reaction:
2Hl(g) ↔ H2(g) + l2(g)’ ΔH = 10 kj;

The concentration of iodine in the equilibrium mixture can be increased by?

  • A. raising the pressure
  • B. raising the temperature
  • C. adding a catalyst
  • D. lowering the pressure
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