FACT/DEFINITION TYPE QUESTIONS
1. The attractive force which holds various constituents
(atoms, ions etc.) together in different chemical species is
called a
(a) chemical bond (b) chemical compound
(c) ionic bond (d) covalent bond
Answer:a
2. The evolution of various theories of valence and the
interpretation of the nature of chemical bonds have closely
been related to the developments in the understanding of
(a) structure of atom
(b) electronic configuration of elements
(c) periodic table
(d) All of the above
Answer:d
💜3. Who provide explanation of valence based on intertness
of noble gases ?
(a) Lewis (b) Kossel-Lewis
(c) Langmuir (d) Sidgwick & Powell
Answer:b
4. In the formation of a molecule which of the following take
part in chemical combination?
(a) cation (b) anion
(c) valence electron (d) inner shell electron
Answer:c
5. Which of the following do(es) not represent correct Lewis
symbols?
:C: O Ne Be B
I II III IV V
(a) I, IV & V (b) II, III & IV
(c) II only (d) II & III
Answer:d
[Hints,Solutions & Explanations @last]
6. The bond formed as a result of the electrostatic attraction
between the positive and negative ions is termed as ...
(a) Chemical bond (b) Electrovalent bond
(c) Co-ordinate bond (d) Covalent bond
Answer:b
[Hints,Solutions & Explanations @last]
7. Cation and anion combines in a crystal to form following
type of compound
(a) ionic (b) metallic
(c) covalent (d) dipole-dipole
Answer:a
[Hints,Solutions & Explanations @last]
8. Electrovalence of calcium and chlorine respectively is
(a) + 2, – 1 (b) + 1, – 1
(c) + 1, – 2 (d) + 2, – 2
Answer:a
[Hints,Solutions & Explanations @last]
9. When a metal atom combines with non-metal atom, the
non-metal atom will
(a) lose electrons and decrease in size
(b) lose electrons and increase in size
(c) gain electrons and decrease in size
(d) gain electrons and increase in size
Answer:d
[Hints,Solutions & Explanations @last]
💜10. Who introduced the term covalent bond ?
(a) Lewis (b) Langmuir
(c) Nyholm and Gillespie (d) Heitler and London
Answer:b
[Hints,Solutions & Explanations @last]
11. Which of the following is/are not the condition(s) for
Lewis dot structure?
(i) Each bond is formed as a result of sharing of an
electron pair between the atoms.
(ii) From the two combining atoms only one atom
contribute electron(s) to the shared pair.
(iii) The combining atoms attain the outer shell noble
gas configurations as a result of the sharing of
electrons.
(a) (i) and (iii) (b) (ii) and (iii)
(c) (ii) only (d) (iii) only
Answer:c
[Hints,Solutions & Explanations @last]
1. (a) Chemical bond is an attractive force, which holds
various constituents (atoms, ions etc.) together in
different chemical species.
2. (d) The evolution of various theories of valence and the
interpretation of the nature of chemical bonds have
closely been related to the developments in the
understanding of structure of atom, electronic
configuration of elements and Periodic Table.
3. (b) Kossel and Lewis provide some logical explanation
of valence which was based on the intertness of
noble gases.
4. (c) In the formation of a molecule, only the outer shell
electrons take part in chemical combination and they
are known as valence electrons.
5. (d) Valence electrons in O = 6
Correct Lewis symbol = O
Similarly, Ne is a noble gas having valence electrons
= 8
Correct Lewis symbol for Ne = :Ne:
: :
6. (b) Electrovalent bond is formed as a result of electrostatic
attraction between the positive and negative ions.
7. (a) The electrostatic force that binds the oppositely
charged ions which are formed by transfer of
electron(s) from one atom to another is called ionic
bond. Cation and anion are oppositely charged
particles therefore they form ionic bond in crystal.
8. (a) Calcium is assigned a positive electrovalence of two,
while chlorine has a negative electrovalence of one.
9. (d) When a metal for example Na combines with a non
metal e.g., Cl2. Following reaction occurs
2Na Cl2 2NaCl
In this process Na loses one electron to form Na+ and
Cl accepts one electron to form Cl–
NaNa e
Cl e Cl
Therefore, in this process Cl gain electrons and hence
its size increases.
10. (b) Langmuir (1919) refined the Lewis postulations by
abandoning the idea of the stationary cubical
arrangement of the octet, and by introducing the
term covalent bond.
11. (c) Each combining atom contributes at least one
electron to the shared pair.
