| 1 |
A reaction in which heat is given out is |
An endothermic reaction
An exothermic reaction
A thermochemical reaction
An energetic reaction
|
| 2 |
When a bond breaks |
Heat is evolved
Heat is absorbs
No change in heat contents takes place
Temperature increases
|
| 3 |
Termochemistry is the study of chemical reaction accompanying |
Heat change
Rate change
Mass change
Volume change
|
| 4 |
Which of the following molecules have multiple bonds |
CH<sub>4</sub>
C<sub>2</sub>H<sub>4</sub>
C<sub>2</sub>H<sub>6</sub>
CCI<sub>4</sub>
|
| 5 |
Which of the following has polar bond |
O<sub>2</sub>
N<sub>2</sub>
HCl
Cl<sub>2</sub>
|
| 6 |
The number of electron pairs shared in carbon tetrachloride molecule is |
2
3
4
1
|
| 7 |
Atoms obey octet rule by sharing-electrons making covalent bonds according to |
Lewis and Kossal theory
Valance bond theory
VSEPR theory
Molecular orbital theory
|
| 8 |
Generally the bond formed by metals with non-metals is |
Ionic
Covalent
Polar
Non- polar
|
| 9 |
An ionic compound M2S3is formed by the metal M,, the metal is |
Ca
Ba
K
Al
|
| 10 |
Atomic number of Al is 13. When it forms ionic bond with oxygen the number of electrons lost by 1 Al atom is |
1
2
3
4
|
| 11 |
All covalent bonds formed between the two atoms are non-polar when |
Covalent bond between two non-metal atoms
Covalent bond between metal and non-metal
Covalent bond between two atoms of same element
Covalent bond between metal atoms
|
| 12 |
The Electro-negatively difference for ionic bond must be greater than |
1.6
1.7
1.8
1.0
|
| 13 |
Electronegativity values of the elements F, CI and Br vary |
F > CI > Br
Br > CI > F
Cl > Br > F
CI > F > Br
|
| 14 |
From the difference between expected bond energies for the normal covalent bond and experimentally determined values Pauling calculated the values of |
Ionization potential of elements
Electron affinity of elements
Electronegativity of elements
Bond length
|
| 15 |
The tendency of an atom to attract shared electron pair towards itself is called |
Covelent bond
Electronegativity
Ionization potential
Electronic affinity
|
| 16 |
When of the following is isolelectronic with krypton |
Ca<sup>++</sup>
Al<sup>+++</sup>
Br<sup>-1</sup>
I<sup>-1</sup>
|
| 17 |
The degree of polarity of molecule is known as its |
Dipole moment
Moment arm
Bond energy
Ionic character
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| 18 |
Generally electron affinities for elements in a period from left to right |
Decreases
Increases
Remain same
Increases alternatively
|
| 19 |
When an electron is absorbed in an empty or partially filled orbital of an atom, the energy released is called |
Ionization energy
Potential energy
Electron affinity
Bond energy
|
| 20 |
In a group the atomic size increase downward due to |
Addition of electronic shells
Increase in the proton number
Repulsion of electrons
All of the above
|
| 21 |
Ca, Mg, Be, Ba, belong to the same group, the order of their ionization energy values is |
Be > Mg> Ca > Ba
Ba > Ca > Mg > Be
Ca > Mg > Be > Ba
Ba > Mg > Ca > Be
|
| 22 |
Ionization energies increase from left to right along the period due to |
Increase in nuclear charge
Repulsion of electron increases
Repulsion of protons increase
Atomic size increase along the period
|
| 23 |
Which of the following charge |
Li
Be
H
He
|
| 24 |
Generally ionization energy of atoms decreases by |
Decreases in atomic size
Increase in atomic size
Increase in nuclear charge
None of these
|
| 25 |
Size of an anion is increased as compared to its atom because of the |
Addition of new shell
Repulsion of electrons in the valence shell
Decrease in nuclear charge
Increase in the unclear charge
|
| 26 |
The ionic bonds are |
Unidirectional
Bi-directional
Non-directional
Multi-directional
|
| 27 |
Shielding effect intervening electrons causes |
Decreases in atomic radii in a period from right to left
Increase in atomic radii in a period from left to righ t
Decrease in atomic radii down the group
Increase in atomic radii down the group
|
| 28 |
When elements of group I react with the elements of group VIA theory form |
Ionic bond
Covalent bond
Polar bond
None
|
| 29 |
Mg becomes isoelectronic with neon when it |
Loses two electrons
Gains two electrons
Loses 1 electron
Gains 1 electron
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| 30 |
Two H-atom combine to form a strong H2molecule due to |
Increase in potential energy
Decrease in potential energy
Energy remains unchanged
Distance is increased
|