| 1 |
The geometry of diamonds is |
tetragonal
cubic
rhombohedral
none of these
|
| 2 |
The molecules of CO2, in dry ice form the |
covalent crystals
molecular crystals
none of these crystals
ionic crystals
|
| 3 |
The nature of crystal of diamond is |
metallic
molecular
covalent
ionic
|
| 4 |
The crystals formed due to London forces of interaction are |
ionic
covalent
molecular
metallic
|
| 5 |
In most of the cases the molecular crystals are |
very soft
soft
extremely hard
sufficiently hard
|
| 6 |
The crystal of diamond is |
ionic
molecular
covalent
metallic
|
| 7 |
Substance that does not show the process of sublimation is |
K2Cr2O7
iodine
naphthalene
NH4CI
|
| 8 |
The number of Na+, ions which surround each Cl- ion in the NaCl crystal lattice is |
8
12
6
10
|
| 9 |
NaCI has face centered cubic structure. The Na ion at the face of the unit cell is shared by |
2-unit cells
4-units cells
only one unit cell
8-unit cells
|
| 10 |
The Cl- ion present at the corner of the unit cell is NaCl crystal, contributes |
1/8 th
1/4 th
1/2 th
1
|
| 11 |
The number of Cl- ions per unit cell of NaCl are |
6
4
2
8
|
| 12 |
lonic solids don't conduct the electrical current because |
ion do not have translatory motion
free electrons are less
the coordination number of the ion is very high
strong covalent bonds are present in their structure
|
| 13 |
lonic solids are characterized by which one of the following properties |
moderately low pressure
high vapour pressure
good conductivity in solid state
solubility in polar solvents
|
| 14 |
Some of crystals are good conductors of heat and electricity, they may be |
ionic in nature
of metallic character
covalent in nature
of molecular nature
|
| 15 |
LiF is a crystalline substance and has |
ionic crystal
metallic crystal
covalent crystal
molecular crystal
|
| 16 |
One of the following is a ionic solid. Which is that? |
Fe
KBr
Diamond
Cr
|
| 17 |
An element from the given below exists as discrete small molecules in the solid state. Which is that? |
Sodium
Silicon
lodine
lron
|
| 18 |
The structure of sodium chloride is |
simple cube
body centered cubic
face centered cubic
depends upon conditions
|
| 19 |
Which property is associated with ionic solids? |
Solubility in polar solvents
Low melting points
Good conductivity in solid state
High vapour pressure
|
| 20 |
In crystal of sodium chloride, a Cl-1 ion present at the corner of cube is shared between how many cubes? |
8
4
6
10
|
| 21 |
What is the co-ordination number of face centered cubic structure? |
12
8
6
10
|
| 22 |
A crystal system in which all three angles and all three edges are different is called |
triclinic
rhombohedral
cubic
hexagonal
|
| 23 |
Structure of CrO4(-2) is' |
triclinic
cubic
octahedral
tetrahedral
|
| 24 |
The most unsymmetrical one in crystal system is |
triclinic
Li, Na, K
monoclinic
hexagonal
|
| 25 |
The hexagonal closed packing is associated with |
Ag, Cu, Au
Zn, Cd, Hg
Li, Na, K
NaCl, KBr
|
| 26 |
Which impurity makes the shape of NaCl crystal needle like |
MgSO4
urea
glucose
MgCO3
|
| 27 |
K2SO4, and K2Cr2O4, are isomorphous solids and exist in |
cubic form
orthorhombic form
trigonal form
tetragonal
|
| 28 |
The transition temperature of tin is |
95.5 C°
13.2 C°
13.2°C
128.5°
|
| 29 |
The existence of an element in more than one form is called |
allotropy
isomorphism
polymorphism
isotropy
|
| 30 |
The transition temperature of KNO3, is |
13.2°C
95.5°C
128°C
32.02°C
|
| 31 |
Polymorphism is shown by AgNO3. Which one of the following options is true for AgNO3? |
Orthorhombic and rhombohedral
Cubic and orthorhombic
Cubic and tetragonal
Monoclinic and hexagonal
|
| 32 |
Which one is an isomorphic pair? |
NaNO3, CaCO3,
NaF, MgO
K2SO4 ,K2Cr2O7
Zn, Cd
|
| 33 |
The examples of a hexagonal system is |
sugar
graphite(a=b not equal to c) {Alpha =beta. not equal to gamma}
sulphur
diamond
|
| 34 |
In diamond, the carbon atoms are arranged in a |
tetrahedral manner
hexagonal manner
square planar manner
octahedral manner
|
| 35 |
Hardness of diamond is attributed to the |
strength of the ionic bonds in the structure
three-dimensional network of covalent bonds
three-dimensional network of covalent bonds
absence of valence electrons in carbon atoms
|
| 36 |
How many allotropic forms are present in carbon? |
Two
Four
Three
Five
|
| 37 |
Which among the following will show anisotropy? |
Wood
Glass
Paper
BeCl2
|
| 38 |
Crystals can be classified into |
7 crystal systems
4 crystal systems
3 crystal systems
14 crystal systems
|
| 39 |
Amount of heat absorbed when one mole of a solid melts into liquid form at its melting point is called: |
heat of vaporization
latent heat of fusion
molar heat of fusion
molar heat of sublimation
|
| 40 |
The boiling point of glycerin at 1 atmospheric pressure is: |
290°C
390°C
190C°
210°C
|
| 41 |
In order to maintain the boiling point of water at 110 C°, the extemal pressure should be |
550 torr
between 500 and 760 tor
between 760 and 1500 torr
any pressure can be maintained
|
| 42 |
Which of following factor affect vapour pressure of a liquid? |
temperature
inter molecules forces
size of the molecules
all of these
|
| 43 |
The boiling of water may be 120°C, when the external pressure is |
greater than 760 torr
less than 760 torr
equal to 760 torr
variable
|
| 44 |
Liquids evaporate at every temperature. When the temperature becomes constant for a liquid, then: |
rate of evaporation is greater than the rate of condensation
the rate of condensation is greater than the rate of evaporation
The rate of condensation and evaporation become equal
it depends upon the nature of the liquid
|
| 45 |
Point out the substance which has maximum vapour pressure at a given temperature? |
Acetone
Water
Ethanol
Acetic acid
|
| 46 |
Vapour pressure of a substance does not depend upon: |
physical state of matter
temperature
intermolecular forces
surface area
|
| 47 |
Which of the following liquid has highest bolling point |
HCI
HBr
H2O
Br2
|
| 48 |
The B.P. of compound is mostly raised by |
dipole-induced dipole interactions
london dispersion forces
intramolecular H-bonding
intermolecular H-bonding
|
| 49 |
The vapour pressure of a liquid depends upon |
amount of the liquid
surface area
temperature
size of container
|
| 50 |
The B.P of glycerine at 760 torr pressure is |
200°C
290C°
250C°
262C°
|
| 51 |
lce occupies more space than liquid water |
9%
10%
11%
12%
|
| 52 |
At freezing point of water, the density decreases due to |
change of bond angles
change of bond lengths
cubic structure of ice
empty spaces present in the structure of ice
|
| 53 |
The long chains of amino acids are coiled around one another into a spiral by |
ionic bond
Van der Waal's forces
hydrogen bonding
overlapping of orbitals
|
| 54 |
H2O and HF are the hydrides of the second period. Fluorine is more electronegative than oxygen. Anyhow, the boiling point of water is greater than that of HF. This is due to: |
water is more polar than HF
water has a bent structure
HF has a zig zag structure after making hydrogen bonding
the number of hydrogen bonds produced by water are greater than that of HF
|
| 55 |
Hydrogen bonding is extensively present in proteins which form the spiral. The hydrogen bond being produced is between |
nitrogen and hydrogen atom
oxygen and hydrogen atom
carbon and hydrogen atom
oxygen and carbon atom
|
| 56 |
Halogens form halogen acids. HF is the weakest among all of them This is due to the reason that |
fluorine is a very small-sized atom
fluorine is highly electronegative atom
there is strong hydrogen bonding in HF
the polarity of HF bond is less
|
| 57 |
The boiling point of H2O is 100°C while that of C2H5-OH is 78.5C°. The reason is that: |
H2O molecules are small-sized
the bond angles at oxygen atom are different
C2H5-group is electron donating
the number of H-bonds are greater in H20, than C2H5-OH
|
| 58 |
Oxygen and sulphur are present in VI-A group of the periodic table The hydride of oxygen i.e., H2O is liquid at room temperature but the hydride of sulphur (H2S) is a gas. This is due to |
greater bond angle of water than Hs
greater bond lengths in HS than H2O
hydrogen bonding in water
acidic character of HS
|
| 59 |
Ice floats on water because |
the hydrogen bonding in ice is stronger than that of in water
empty spaces are left in ice
ice has two-dimensional structure
the bond length of the oxygen and hydrogen bond is different in water and ice
|
| 60 |
H-bonding is maximum in: |
ethanol
benzene
diethyl ether
water
|