JAMB CHEMISTRY PRACTICE QUESTIONS AND ANSWERS [C.B.T]

GOOD EVENING EVERYONEJAMB CHEMISTRY PRACTICE QUESTIONS AND ANSWERS [C.B.T]

1. By chemical means, chemical elements cannot be broken down into
   A. metals
   B. non-metals
   C. smaller substances
   D. metalloids

2. The number of electrons are always equal to number of protons in a
   A. neutral atom
   B. positive ion
   C. negative ion
   D. isotope

3. Brass is an example of an/a
   A. alloy
   B. compound
   C. mixture
   D. element

4. Isotopes differ in the number of
   A. electrons
   B. protons
   C. neutrons
   D. anti neutrino

5. The number of isotopes occupied by carbon is

A,4
B. 7
C. 2
D. 7

1. Atom was a name given by
   A. Mendeleev
   B. Bohr
   C. Rutherford
   D. Democritus

2. The rate of a chemical reaction is NOT affected by one of these factors
   A. colour
   B. concentration
   C. presence of light
   D. surface area

3. Pipe-borne water is usually chlorinated in order to
   A. coagulate sediments in the water
   B. improve taste of the water
   C. kill harmful bacteria in the water
   D. make it pure

4. The separation of petroleum fractions depends on the differences in their
   A. melting points
   B. molar masses
   C. solubilities
   D. boiling points

10 What type of bond holds hydrogen fluoride molecules together when forming larger aggregate?
A. Covalent
B. Dative
C. Hydrogen
D. Ionic

1. The high boiling point of hydrogen fluoride can be explained in terms of
   A. covalent bonds.
   B. dative bonds.
   C. dipole-dipole bonds
   D. hydrogen bonds

2. Which of the following compounds is unsaturated?
   A. Cyclohexane
   B. Methoxyethane
   C. 1 ,2-dibromoethane
   D. 3-methylbut-l-ene ✔️

3. Which of the following metals would readily displace hydrogen from steam?
   A. Copper
   B. Lead
   C. Magnesium
   D. Silver

4. The volume occupied by 0.4 g of hydrogen gas at s.t.p. is [H = 1. 00; Molar volume at s.t.p. = 22.4 dm³]
   A. 2.24 dm³
   B. 4.48dm³
   C. 22.4dm³
   D. 44.8dm ³

5. When a substance changes directly from the solid state to the gaseous state without forming a liquid, the substance is said to
   A. condense
   B. evaporate
   C. sublime
   D. precipitate

6. At ordinary temperature H₂O is a liquid while H₂S is a gas. This is because H₂O has
   A. weak intermolecular forces holding its molecules together
   B. strong hydrogen bonds holding its molecules together ✔️
   C. induced dipoles induced dipole forces between its molecules
   D. ionic force between its molecules

7. The postulate that molecules are in constant random motion best explains why liquids
   A. can undergo solidification
   B. maintain their volumes
   C. are incompressible
   D. have no characteristic shape

8. Average kinetic energy of a gas molecule is
   A. Inversely proportional to the square of its absolute temperature
   B. Directly proportional to the square root of its absolute temperature
   C. Directly proportional to its absolute temperature
   D. Directly proportional to square of absolute temperature

19 The oxidation number of Fe in [Fe(CN)₆]³⁻ is
A. +3
B. +2
C. -2
D. -3

1. Which one proposes a relationship between the combining volumes of gases with respect to the reactants and gaseous products.
   A. Avogadro’s number
   B. P₁V₁ = P₂V₂
   C. V₁T₂ = V₂T₁
   D. Gay Lussac’s law