THE MODERN SCHOOL

BARMER

Half yearly 11
CLASS 11 - CHEMISTRY

Time Allowed : 180 mins Maximum Marks : 73

Section A

1 Orbital angular [1]

momentum depends
on ________.

a) m and s

b) n and m

c) l

d) n and l

2 Which of the following [1]

will have the most
negative electron gain
enthalpy and which
one the least negative?
P, S, Cl, F.

a) None of these

b) P,Cl

c) Cl, P

d) P,S

3 The first ionisation [1]

enthalpies of Na, Mg, Al
and Si are in the order:

a) N a> M g> A l<S i

b) N a> M g> A l>S i

c) N a< M g< A l<S i

 d) N a< M g> A l<S i

4 Electronic [1]
configurations of four
elements A, B, C and D
are given below:

1. 1s❑2 2s ❑2 2p
6
❑
2. 1s❑2 2s ❑2 2p
4
❑
3. 1s❑2 2s ❑2 2p
❑ 3s ❑
6 1

4. 1s❑2 2s ❑2 2p
5
❑
Which of the following
is the correct order of
increasing tendency to
gain electron?

a) D < A < B < C

b) D < B < C < A

c) A < B < C < D

d) A < C < B < D

5 Which one of the [1]

following is
isoelectronic with Ne?

a) mg❑2+¿ ¿

b) Al❑3+¿ ¿

c) N❑3 −

d) All of these

6 Which of the following [1]

is the correct IUPAC
name?

a) 5 - Ethyl - 4, 4 -
dimethylheptane
 b) 4, 4 - Bis(methyl) -
3 - ethylheptane

c) 3 - Ethyl - 4,4 -
dimethylheptane

d) 4, 4 - Dimethyl - 3 -
ethylheptane

7 The IUPAC name for [1]

is ________.

a) 4 - oxopentanoic
acid

b) 1 - hydroxypentane
- 1,4 - dione

c) 1 - carboxybutan - 3
- one

d) 1, 4 - dioxopentanol

8 The reduction in the [1]

attractive interaction
of an electronin the
outer shelland the
nucleus due to the
presence of electrons
in the inner shellsis
known as _________.

a) Aufbau rule

b) exchange energy

c) Hund’s rule

d) screening effect

9 Give the number of [1]

electrons in the
+¿¿
species, O❑2 and O2 .

a) 32 and 16

b) 16 and 14
 c) 16 and 8

d) 16 and 15

10 State true or false: [1]

All molecules with
polar bonds have
dipole moment.

11 Which of the following [1]

elements does not
show
disproportionation
tendency?

a) Br

b) F

c) I

d) Cl

12 The oxidation number [1]

of hydrogen in LiH,
NaH and CaH❑7 is_____.

a) - 1

b) - 2

c) 1and 2

d) - 1 and - 2

13 Number of π bonds and [1]

σ bonds present in the
following structure is:

a) 6, 19

b) 5, 19

c) 5, 20

d) 4, 20
14 Which of the following [1]
angle corresponds to
sp❑2 hybridisation?

a) 109°

b) 180°

c) 90°

d) 120°

15 Which of the following [1]

has maximum number
of lone pairs associated
with Xe?

a) XeF❑2

b) XeF❑6

c) XeF❑4

d) XeO❑3

16 Rank the following [1]

bonds in order of
increasing polarity: H -
N, H - O, H - C.

a) H - C < H - N < H - O.

b) H - C < H - O < H -
N.

c) H - O < H - N < H - C

d) H - N < H - O < H - C

17 Choose the correct [1]

bond - line formula for

a)

b)

c)
 d)

Section B

18 Draw the structure of [2]

the following species
ClO❑4 ❑− .
19 Calculate the energy of [2]
one mole of photons of
radiation whose
frequency is 5× 10 ❑14
Hz.
20 Define ionization [2]
enthalpy and electron
gain enthalpy.
21 Give four examples of [2]
species which are
isoelectronic with Ca
❑2+¿ ¿ .
22 Why does fluorine not [2]
show
disproportionation
reaction?
Section C

23 Write the structural [3]

formula of

1. o - ethylanisole,

2. p - nitroaniline

3. 4 - ethyl - 1 -
fluoro - 2 -
nitrobenzene

24 Define hydrogen [3]

bonds. Is it weaker or
stronger than the van
der Waal’s forces?
25 Calculate the oxidation [3]
state of

1. Mnin KMnO❑4
and
 2. N in N O−3 .

26 1. The electrode [3]

reduction
potentials of
four metallic
elements A, B, C,
and D are
respectively
+0.79, - 0.74,
1.08 and - 0.31
V. Arrange these
in order of
decreasing
electropositivity
character.

2. Out of
aluminium and
silver vessel
which one will
be more
suitable to store
1 M HCI solution
and why?E ❑o
$_{ AI$ = -
1.66 V, E ❑o $_{
Ag$ = + 0.80 V

27 Calculate the energy [3]

and frequency of the
radiation emitted when
an electron jumps from
n = 3 to n = 2 in a
hydrogen atom.
28 A photon of [3]
wavelength 4× 10 ❑−7
m strikes on the metal
surface, the work
function of metal being
2.13 eV. Calculate

1. the energy of
the photon (eV),

2. the kinetic
 energy of
emission,

3. the velocity of
the
photoelectron.
(1 eV = 1.6020×
10 ❑−19 J).

29 Write the Lewis dot [3]

structure of the CO
molecule.
30 Give the common name [3]
of

1. ethoxyethane

2. ethanoic acid

3. Methyl benzene

Section D

31 Read the text [4]

carefully and answer
the questions: In the
modern periodic table,
elements are arranged
in order of increasing
atomic numbers which
is related to the
electronic
configuration.
Depending upon the
type of orbitals
receiving the last
electron, the elements
in the periodic table
have been divided into
four blocks, viz, s, p, d
and f. The modern
periodic table consists
of 7 periods and 18
groups. Each period
begins with the filling
of a new energy shell.
In accordance with the
Aufbau principle, the
seven periods (1 to 7)
have 2, 8, 8, 18, 18, 32
and 32 elements
respectively. The
seventh period is still
incomplete. To avoid
the periodic table being
too long, the two series
of f - block elements,
called lanthanoids and
actinoids are placed at
the bottom of the main
body of the periodic
table.

1. The element
with atomic
number 57
belongs to
which block?

2. What is the
outermost
electronic
configuration of
last element of
the p - block in
6❑t h period?

3. Can an element
with atomic
number 126, if
discovered be
accommodated
in the present
set up of the
long form of the
periodic table

4. What is the
electronic
configuration of
the element
which is just
above the
element with
 atomic number
43 in the same
group?

32 Read the text [5]

carefully and answer
the questions: A large
number of orbitals are
possible in an atom.
Qualitatively these
orbitals can
bedistinguished by
their size, shape and
orientation. An orbital
of smaller size means
there is more chance of
finding the electron
near the nucleus.
Similarly, shape and
orientation mean that
there is more
probability of finding
the electron along with
certain directions than
along others.The
principal quantum
number determines the
size and to large extent
the energy of the
orbital.Azimuthal
quantum number,‘l’ is
also known as orbital
angular momentum or
subsidiary quantum
number. Each shell
consists of one or more
subshells or sub -
levels. The number of
sub - shells in a
principal shell is equal
to the value of
n.Magnetic orbital
quantum number. The
fourth quantum
number is known as
the electron spin
 quantum number (m❑s
). An electron spins
around its own axis,
much in a similar way
as the earth spins
around its own axis
while revolving around
the sun.

1. What does
magnetic orbital
number
describe?

2. Write the value

of four quantum
numbers for the
valence electron
of the sodium
atom.

3. Out of 6s and 4f
orbitals, which
has higher
energy and
why?

4. What is the total

number of
orbitals
associated with
the principal
quantum
number n = 3 ?

Section E

33 Write the important [3]

conditions required for
the linear combination
of atomic orbitals to
form molecular
orbitals.
34 What is the effect on [5]
bond order of the
following processes
on the bond order in
 N - , and 0❑2 ? (i) N❑2
→ N ❑+¿¿ ❑2 + e ❑– (ii)
0 ❑2 → O ❑+¿¿ ❑2 + e
❑ EXPLAIN WITH
–

MOT DIAGRAMS.
35 Balance the [5]
following equation by
the half reaction
method Zn (s) + NO❑3
❑ → Zn ❑ (aq)+
– 2+¿ ¿

NH $_{ 4$ (aq) + H
❑2 O (In acid
solution)