Validity of Assumptions

Q.

Real gases behave much like an ideal gas at________

Q.

What are the characteristics of an ideal gas?

Q.

How does the kinetic theory explain Charles Law?

Q.

What are the postulates of kinetic molecular theory?

Q. A gas behaves more closely to an ideal gas at and .

1. Low pressure
2. High pressure
3. Low temperature
4. High temperature

Q.

What is an example of Kinetic theory of matter?

Q.

According to kinetic theory of gases, 0 kelvin is the temperature at which for an ideal gas, the internal energy is

Q. A gas behaves more closely as an ideal gas at
(a) low pressure and low temperature
(b) low pressure and high temperature
(c) high pressure and low temperature
(d) high pressure and high temperature.

Q. What are the Basic concepts of Kinetic molecular theory?

Q.

In the kinetic theory of gases, we try to relate macroscopic properties of a gas, like pressure, volume and temperature to its microscopic properties (properties of each atom or molecule) like particle speeds, momenta, kinetic energies, etc. Which of the following is/are incorrect assumption(s) for building the theory?

Q.

This section contains 1 Assertion-Reason type question, which has 4 choices (a), (b), (c) and (d) out of which ONLY ONE is correct.

इस खण्ड में 1 कथन-कारण प्रकार का प्रश्न है, जिसमें 4 विकल्प (a), (b), (c) तथा (d) दिये गये हैं, जिनमें से केवल एक सही है।

A : A small ball is moving in the shape of a conical pendulum with the help of an ideal string (as shown) with constant speed.
A : एक छोटी गेंद आदर्श डोरी की सहायता से (दर्शाए अनुसार) एक शंक्वाकार लोलक की आकृति में नियत चाल से गतिशील है।


Angular momentum of ball about point of suspension will remains constant.
निलम्बन बिन्दु के सापेक्ष गेंद का कोणीय संवेग नियत रहेगा।

R : If there is no external force acting on a system of particles, then the velocity of centre of mass remains constant (total mass of system is constant).
R : यदि कणों के एक निकाय पर कोई बाह्य बल क्रियाशील नहीं है, तब द्रव्यमान केन्द्र का वेग नियत रहता है (निकाय का कुल द्रव्यमान नियत है)।

1. Both (A) and (R) are true and (R) is the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं तथा (R), (A) का सही स्पष्टीकरण है
2. Both (A) and (R) are true but (R) is not the correct explanation of (A)
   
   (A) तथा (R) दोनों सही हैं लेकिन (R), (A) का सही स्पष्टीकरण नहीं है
3. (A) is true but (R) is false
   
   (A) सही है लेकिन (R) गलत है
4. (A) is false but (R) is true
   
   (A) गलत है लेकिन (R) सही है

Q. A gas is heated at constant volume, temperature of gas becomes 4 times of initial value, then mean free path for molecules

1. becomes half
2. becomes double
3. remains same
4. becomes $\sqrt{2}$ times

Q. The mean free path for gas molecules with molecular diameter $d$ and number density $n$ is proportional to

1. $\frac{1}{d}$
2. $d^2$
3. $\frac{1}{n}$
4. $\frac{1}{n^2}$

Q.

Are all gases ideal?

Q.

What does statistical mechanics mean?

Q. What are the kinetic molecular theory? State in points.

Q. Let C_v and C_p denote the molar heat capacities of an ideal gas at constant volume and constant pressure respectively. Which of the following is a universal constant?
(a) $\frac{C_p}{C_v}$
(b) C_pC_v
(c) C_p − C_v
(d) C_p + C_v

Q. An ideal gas changes from state a to state b as shown in Fig. What is the work done by the gas in the process?

1. zero
2. positive
3. negative
4. infinite

Q.

A real gas behaves as an ideal gas at

1. At high temperature and low pressure

2. At low temperature and high pressure

3. At normal temperature and pressure

4. At all temperatures and pressures

Q. A real gas behaves like an ideal gas if its

1. Pressure is high and temperature is low
2. Pressure is low and temperature is high
3. Pressure and temperature are both high
4. Pressure and temperature are both low

Q. A real gas behaves like an ideal gas if its.

1. Both pressure and temperature are high
2. Both pressure and temperature are low
3. Pressure is low and temperature is high
4. Pressure is high and temperature is low

Q. The state of a gas is time dependent.

1. True
2. False

Q. A gas behaves more closely to an ideal gas at and .

1. Low pressure
2. High pressure
3. Low temperature
4. High temperature

Q.

Imagine a gravity free laboratory, in outer space, where you are asked to study the motions of a large number of marbles kept in a transparent cubical jar, as you give the jar quick, small jerks in random directions. You will observe, that after giving a sufficient number of jerks, the marbles start moving rather chaotically, i.e., each marble bounces off other marbles every now and then, and takes a random trajectory between two points due to these collisions. You seem to have given some kinetic energy to each marble, when the jar was being shaken. What happens when you release the jar suddenly, leaving it suspended in space? Assume all collisions between the marbles to be perfectly elastic.

1. The jar stays still, as all the kinetic energy is now being used only by the marbles inside

2. The moment you stop shaking and leave the jar it starts moving in a particular direction along a straight line

3. The jar starts shaking with small, random vibrations

Q. A gas behaves more closely to an ideal gas at and .

1. Low pressure
2. High pressure
3. Low temperature
4. High temperature

Q.

In the kinetic theory of gases, we try to relate macroscopic properties of a gas, like pressure, volume and temperature to its microscopic properties (properties of each atom or molecule) like particle speeds, momenta, kinetic energies, etc. Which of the following is/are incorrect assumption(s) for building the theory?

1. Molecules will experience inter-molecular forces of electrostatic attraction or repulsion, because of valence electrons and nuclear protons

2. A collision between two molecules, or a molecule and a wall preserves net kinetic energy and momentum

3. At equilibrium (i.e., after the system has been left undisturbed for a long time), the number of molecules inside a particular $1c{m}^3$ will be the same for any other $1c{m}^3$, inside the containing volume.

4. Temperature is a property of the average internal energy of all the molecules, not of one molecule.

Q.

Imagine a gravity free laboratory, in outer space, where you are asked to study the motions of a large number of marbles kept in a transparent cubical jar, as you give the jar quick, small jerks in random directions. You will observe, that after giving a sufficient number of jerks, the marbles start moving rather chaotically, i.e., each marble bounces off other marbles every now and then, and takes a random trajectory between two points due to these collisions. You seem to have given some kinetic energy to each marble, when the jar was being shaken. What happens when you release the jar suddenly, leaving it suspended in space? Assume all collisions between the marbles to be perfectly elastic.

1. The jar stays still, as all the kinetic energy is now being used only by the marbles inside
2. The moment you stop shaking and leave the jar it starts moving in a particular direction along a straight line
3. The jar starts shaking with small, random vibrations

Q. Gases are good conductors of electricity at :

1. low pressure
2. high pressure
3. low temperature
4. high temperature

Q. Assertion :At STP or any identical temperature and pressure, the volume occupied by a definite mass of any gas are identical. Reason: Equal mole of any monoatomic gas at the same temperature have the same average kinetic energy.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. The behaviour of the gases, which can be easily liquified, is like that of the

1. triatomic gases
2. ideal gases
3. van der Waals gases
4. all of the above