JEE Main Chemistry - States of Matter
Exam Duration: 60 Mins Total Questions : 30
Real gases approach ideal behaviour at
- (a)
high temperature and low pressure
- (b)
low temperature and low pressure
- (c)
high temperature and high pressure
- (d)
critical temperature
When the pressure gradient and temperature are held constant the rates of effusion of CO and N2 will be in the ratio
- (a)
1:2
- (b)
2:1
- (c)
1:1
- (d)
1:4
To which one of the following Dalton's law of partial pressure is not applicable?
- (a)
SO2 and CO2 at room temperature
- (b)
N2 and H2 at room temperature
- (c)
SO2 and O2 at room temperature
- (d)
HCl and NH3 at room temperature
The temperature of a certain mass of a gas was increased from \({ 40 }^{ \circ }C\ to\ {41 }^{ \circ }C\) at constant pressure. The volume of the gas
- (a)
will increase by 1/273 of its volume at 273 K
- (b)
will increase by1/273of its volume at \({ 40 }^{ \circ }C\)
- (c)
will remain constant
- (d)
will increase, but the increase in volume cannot be predicted
Helium atoms is two times heavier than a hydrogen molecule. At 300 K, the average K.E. of a helium atom is
- (a)
equal to that of hydrogen atom
- (b)
half that of hydrogen molecule
- (c)
same as that of hydrogen molecule
- (d)
two times that of hydrogen molecule
A mixture of three gases A (density 0.90), B (density 0.178) and C (density 0.42) are enclosed in avessel at constant temperature. When the equilibrium is established
- (a)
the gas A will be at the top of the vessel
- (b)
the gas B will be at the top of the vessel
- (c)
the gas C will be at the top of the vessel
- (d)
the gases will mix homogenously throughout the vessel
Which one of the following is a postulate of kinetic theory?
- (a)
gases combine in single ratio of their volume
- (b)
The pressure of the gas is due to the hits recorded by the moving molecules on the walls of the container
- (c)
Gases are made of particles called atoms
- (d)
NONE OF THE ABOVE
The rates of diffusion of SO2, CO2, PCl3, and SO3 are in the order
- (a)
\(PCl_3>SO_3>SO_2>CO_2\)
- (b)
\(CO_2>SO_2>PCl_3>SO_3\)
- (c)
\(SO_2>SO_3>PCl_3>CO_2\)
- (d)
\(CO_2>SO_2>SO_3>PCl_3\)
7.0 gm of N2 occupies 8.4 litre at \({ 20 }^{ \circ }C.\) What is the pressure of the gas under these conditions?
- (a)
0.71 atm
- (b)
0.355 atm
- (c)
3.55 atm
- (d)
77.1 atm
The molecule of SO2 is four times heavier than the molecule of CH4. The root mean square velocity for CH4 molecule is
- (a)
one-fourth that of SO2 molecule
- (b)
equal to that of SO2 molecule
- (c)
twice that of SO2 molecule
- (d)
four times that of SO2 molecule
Schottky defect is caused due to
- (a)
missing cation
- (b)
missing anion
- (c)
missing cation and anion
- (d)
presence of an ectra ion
Which of the following is isotropic?
- (a)
alcohol
- (b)
copper sulphate
- (c)
calcium oxide
- (d)
rhombic sulphur
The phenomenon in which different chemical substances exhibit the same crystalline from is called
- (a)
Isomorphism
- (b)
Polymorphism
- (c)
Enantiotropic
- (d)
Monotropic
Which is not correct about sodium chloride crystal lattice?
- (a)
Cl- forms CCP structure and Na+ occupies octahedral holes
- (b)
Co-ordination number of chloride ion is 6
- (c)
A single unit cell has one NaCl unit in it
- (d)
Coordination number of Na+ is 6
The number of equidistant oppositely charged ions in NaCl crystal is
- (a)
8
- (b)
6
- (c)
4
- (d)
2
Which of the following defects in the crystals lower its density?
- (a)
Schottky
- (b)
Frenkel
- (c)
Interstitial
- (d)
F-centres
A compound formed by elements A and B crystallises in the cubic structure, where A atoms are at the corners of a cube, while B atoms are at the face ventres. the formula of the compound would be?
- (a)
AB
- (b)
AB2
- (c)
AB3
- (d)
NONE OF THESE
One litre of gas weighs 2 g at 300 K and 1 atm, pressure. If the pressure is made 0.75 atm, at which of the following temperatures will one litre of the same gas weigh one gram?
- (a)
450 K
- (b)
600 K
- (c)
800 K
- (d)
900 K
Silicon doped with arsenic is an example of which type of semiconductor?
- (a)
p-type
- (b)
n-type
- (c)
n, p type
- (d)
intrinsic
The edge length of face centred unit cubic cell is 508 pm; if the radius of the cation is 110 pm, the radius of the anion is
- (a)
110 pm
- (b)
144 pm
- (c)
618 pm
- (d)
398 pm
The CN of Cl- in crystals of NaCl (A) and CsCl (B) is
- (a)
4 in A and 6 in B
- (b)
6 in A and 8 in B
- (c)
8 in A and 8 in B
- (d)
8 in A and 6 in B
The temperature of 2.0 g of hydrogen was raised from \({ 0 }^{ \circ }C\) to \({ 273 }^{ \circ }C\) at constant pressure. Which of the following statements is correct?
- (a)
the r.m.s. velocity increases by a factor of \(\surd 2\)
- (b)
the mean free path remains constant
- (c)
the average K.E. increases by a factor of 273.
- (d)
the most probable velocity remains unchanged
A mixture of equal volumes of H2 and Cl2 were exposed to ultraviolet light at constant pressure. Pick the correct statement.
- (a)
The volume of the mixture decreases by a factor of 2.
- (b)
The volume of the mixture increases by a factor of 2.
- (c)
The volume remains unchanged as there is no chemical reaction
- (d)
A chemical reaction occurs but there is no volume change.
A gaseous mixture contains oxygen and nitrogen in the ratio of 1 : 4 by weight. Therefore the ratio of their number of molecules is
- (a)
1 : 4
- (b)
1 : 8
- (c)
17 : 32
- (d)
3 : 6
At \({ 0 }^{ \circ }C,\) the density of a geseous oxide at 2 bar is same as that of nitrogen at 5 bar. The molecular mass of gaseous oxide would be
- (a)
56 g mol-1
- (b)
84 g mol-1
- (c)
28 g mol-1
- (d)
70 g mol-1
Two flasks A and B of 1 L capacity each containing SO2 and Br2 respectively maintained at 340 K and pressure of 1.5 atm. If number of Br2 molecules in flask B is N; the total number of atoms in flask A would be
- (a)
N/2
- (b)
N
- (c)
2N
- (d)
3N
If the absolute temperature of a gas having volume V cm3 is doubled and the pressure is reduced to half, the final volume would be
- (a)
2V
- (b)
4V
- (c)
8V
- (d)
16V
A student forgot to add the reaction mixture to the round bottomed flask at \({ 27 }^{ \circ }C\) but put it on the flame. After a lapse of time, he realised his mistake; using a pyrometer he found the temperature of the flask was \({ 477 }^{ \circ }C.\) The fraction of air expelled would be
- (a)
\(1\over 4\)
- (b)
\(2\over 3\)
- (c)
\(1\over 3\)
- (d)
\(3\over 5\)
The compressibility factor for an ideal gas is
- (a)
1.0
- (b)
1.2
- (c)
1.5
- (d)
\(\infty \)
Na and Mg crystallise in BBC and FCC type crystals respectively, then the number of atoms of Na and Mg present in the unit cell of their respective crystal is
- (a)
4 and 2
- (b)
9 and 14
- (c)
14 and 9
- (d)
2 and 4