Chemistry JAMB, WAEC, NECO AND NABTEB Official Past Questions

610

The following molecules have double covalent bonds between two atoms except?

  • A. oxygen
  • B. carbon (IV)oxide
  • C. ethene
  • D. water
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611

Which of the following solids would not decompose on heating?

  • A. Ammonium chloride
  • B. Lead (i) trioxonitrate (V)
  • C. Potassium trioxocarbonate (IV)
  • D. Sodium hydrogen trioxocarbonate (IV)
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612

The boiling point of pentane is higher than that of propane because?

  • A. carbon-carbon single bonds are stronger than carbon-hydrogen bonds.
  • B. Pentane has more covalent bonds to break
  • C. Pentane does not burn easily as propane
  • D. The intermolecular forces in pentane are stronger than those of propane
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613

A factor that is considered most important when siting a chemical industry is?

  • A. nearness to other industrial establishments
  • B. nearness to raw materials
  • C. favourable climate conditions
  • D. availability of storage facilities
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614

Which of the following pairs of elements has the greatest difference in electronegativity?

  • A. Na and F
  • B. Na and CI
  • C. Na and Br
  • D. Na and I
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615

A balanced chemical equation is based on the law of?

  • A. Periodicity
  • B. Constant composition
  • C. Multiple proportion
  • D. Conservation of mass
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616

The oxidation state of chlorine in NaClO\(_3\) is?

  • A. +1
  • B. +3
  • C. +5
  • D. +6
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617

When an ionic bond is broken, bonding electrons are

  • A. shared between participating atoms
  • B. gained by the most electropositive atom
  • C. gained by the most electronegative atom
  • D. lost by both participating atoms.
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618

Group VIl elements in their combined states are called?

  • A. Halogens
  • B. Anions
  • C. Halide
  • D. Cations
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619

The most suitable process of obtaining water from an aqueous solution of sugar i

  • A. Crystallization
  • B. Distillation
  • C. Filtration
  • D. Decantation
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620

Which of the following pairs of properties of alkali metals decreases down the group?

  • A. First ionization energy and reactivity
  • B. melting point and atomic radius
  • C. Reactivity and electronegativity
  • D. First ionization energy and melting point
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621

The high solubility of ethanol in water is due to?

  • A. its low boiling point.
  • B. its low freezing point.
  • C. its covalent nature
  • D. hydrogen bonding
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622

Equal masses of calcium trioxocarbonate(iv) were added to dilute hydrochloric acid at the temperature specified. Under which of the following conditions would the reaction be slowest?

  • A. Calcium trioxocarbonate ( iv ) chips a 20°C
  • B. CalcIum trioxocarbonate (IV) chips at 40°C
  • C. Calcium trioxocarbonate (IV) powder at 20'C
  • D. Calcium trioxocarbonate (IV) powder at 40'C
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623

What is the mass of silver deposited when 24,125 C of electricity is passed through a solution or silver salt.

[Ag = 108, IF = 96,500 C ]

  • A. 432g
  • B. 108g
  • C. 54g
  • D. 27g
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624

What quantity of electrons is lost when one mole of iron (II) ions is oxidized to iron (III) ?

  • A. 0 mole
  • B. 3 moles
  • C. I mole
  • D. 2 moles
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625

Which or the following products could be formed during incomplete combustion of a hydrocarbon.

i.Carbon ii. Hydrogen III. Carbon (Il) oxide

  • A. I only
  • B. I and II only
  • C. I and III only
  • D. II and III only
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626

Which or the following substances is a polypeptide?

  • A. Starch
  • B. Glycogen
  • C. Protein
  • D. Fats
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627

 

The IUPAC name of the compound represented by the structure below is ?

 

  • A. 2- chloro but-I ,3-diene.
  • B. But-1,3-chlorodiene.
  • C. 2-chloro but-diene.
  • D. 3 -chloro but -1.3-diene.
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628

Which of the following substances is an example of a fine chemical?

  • A. Sodium hydroxide
  • B. Hydrochloric acid
  • C. Ethylene
  • D. Ammonia
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629

Kipps  apparatus can be used to prepare?

  • A. H\(_2\)
  • B. NH\(_3\)
  • C. O\(_2\)
  • D. H\(_2\)S
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630

The group to which elements belong in the periodic table is determined by the number?

  • A. electrons
  • B. core electrons
  • C. valence shells
  • D. valence electrons
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