Physics

Thermodynamics and Gas Laws

626 Questions

Thermodynamics and gas laws questions test the understanding of ideal gas behavior, work done during thermodynamic processes, and specific heat ratios. Key areas include isothermal, adiabatic, and isobaric expansions along with real gas deviations. These mathematical physics concepts are standard in engineering and general science competitive exams.

Ideal gas equationIsothermal and adiabatic processesThermodynamic workGas kinetic theoryReal gas behavior

Thermodynamics and Gas Laws Questions

Multiple choice chemistry states of matter: gaseous and liquid states gay lussac's law gas laws states of matter

Which one proposes a relationship between the combining volumes of gases with respect to the reactants and gaseous products.

  1. Avogadro's number
  2. $P _1V _1=P _2V _2$
  3. $V _1T _2=V _2T _1$

  4. Dalton's Theory

  5. Gay-Lussac's Law
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Gay-Lussac's Law proposes a relationship between the combining volumes of gases with respect to the reactants and gaseous products. According to this law, when gases react together to produce gaseous products, the volumes of reactants and products bear a simple whole number ratio with each other, provided volumes are measured at same temperature and pressure.

Multiple choice chemistry states of matter: gaseous and liquid states gay lussac's law gas laws states of matter

Gay Lussac's Law of combining volumes is applicable for combustion of carbon.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Gay Lussac's Law of Combining Volumes. Gay Lussac's Law of Combining Volumes states that whengases react, they do so in volumeswhich bear a simple ratio to one another, and to the volume of the product(s) formed if gaseous, provided the temperature and pressure remain constant.
Multiple choice chemistry states of matter: gaseous and liquid states gay lussac's law gas laws states of matter

To use Gay-Lussac's Law, which of the following needs to remain constant?

  1. Volume and the number of moles of a gas

  2. Pressure and temperature

  3. Temperature and the number of moles of a gas

  4. Pressure and the number of moles of a gas

  5. Temperature and volume
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$P \propto T $
At constant volume and number of moles of a gas, the pressure is directly proportional to the absolute temperature.

Hence, option $A$ is correct.

Multiple choice applications of adsorption adsorption adsorption and colloids surface chemistry chemistry

Which of the following is most favourable for vander waals  adsorption?

  1. high pressure and high temperature

  2. low pressure and low temperature

  3. low pressure and high temperature

  4. high pressure and low temperature
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Physisorption is Vanderwaals adsorption, it occurs at high pressure and low temperature conditions.

Multiple choice conduction in metals and non-metals thermal energy transfers physics

It is required to double the pressure of a gas contained in steel cylinder by heating. If the initial temperature of the gas is ${ 27 }^{ 0 }C$, the temperature upto which it the gas is to be heated is 

  1. ${ 327 }^{ 0 }C$
  2. ${ 273 }^{ 0 }C$
  3. ${ 108}^{ 0 }C$
  4. ${ 54 }^{ 0 }C$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For a gas in a rigid container (constant volume), Gay-Lussac's law states that pressure is directly proportional to absolute temperature (P1/T1 = P2/T2). Given initial temperature T1 = 27 + 273 = 300 K and P2 = 2P1, the final temperature T2 = 2 * 300 = 600 K. Converting back to Celsius gives 600 - 273 = 327 degrees Celsius.

Multiple choice chemistry combustion structure of flame flame combustion, fuels and flame

In LPG cylinder, the gas is liquefied by ___________.

  1. increasing volume

  2. applying pressure

  3. increasing temperature

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

LPG (Liquefied Petroleum Gas) is stored in cylinders under high pressure, which forces the gas molecules together to change their state from gaseous to liquid.

Multiple choice physics heat energy transfers heat energy heat, internal energy and work internal energy

How much heat energy in joules must be supplied to $14\ gms$ of nitrogen at room temperature to rise its temperature by $ 40^o C $ at constant pressure?
(Mol.wt.of $ N _2 = 28 gm , R = constant $)

  1. $50R$
  2. $60R$
  3. $70R$
  4. $80R$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Given,

Mass of nitrogen, $m=14gms$
Temperature, $T=40^0C$
Molecular weight of nitrogen, $M=28gms$
Now,
We know that,
Amount of heat supplied, $Q = n{C _p}\left( {dT} \right)$
No, of moles, $n = \frac{m}{M}$
$\therefore Q = \frac{m}{M}{C _p}dT$
$\begin{array}{l} =\frac { { 14 } }{ { 28 } } \times \frac { { 7R } }{ 2 } \times 40 \ =70R \end{array}$
Hence,
Option $C$ is correct answer.

Multiple choice physics measurement and effects of heat sources of heat introduction to heat measuring temperature

For a gm molecule of an ideal gas

  1. ${PV}/{T} = 2$ calories
  2. ${PV}/{T} = 4.2$ calories
  3. ${PV}/{T} = 4.31$ calories
  4. ${PV}/{T} = 4.2 \times {10}^{7}$ ergs
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

For one gram mole of an ideal gas, the ideal gas equation is PV = RT. The universal gas constant R is approximately 2 calories per mole per Kelvin, making PV/T equal to 2 calories.

Multiple choice biology water a precious resource water cycle earth's energy budget bio-geo chemical cycles in nature solar energy and its applications

What would be temperature of gaseous hydrocarbon in condensation?

  1. Higher temperature

  2. Lower temperature

  3. Normal temperature

  4. Extremely high temperature
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Condensation is the process where a gas turns into a liquid. This phase change requires the removal of heat, meaning the substance must be at a lower temperature than its boiling point to transition.

Multiple choice chemistry how far? how fast? collision theory collision theory of chemical reactions rate of chemical reaction

If X is the total number of collisions which a gas molecule registers with other molecules per unit time under particular conditions, then the collision frequency of the gas containing N molecules per unit volume is?

  1. X/N

  2. NX
  3. $2NX$
  4. $NX/2$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The collision frequency Z is related to the number of collisions per unit volume. For a gas with N molecules per unit volume, the collision frequency is given by Z = (sqrt(2) * pi * d^2 * v_avg * N^2) / 2. The standard expression for collision frequency per unit volume is proportional to N^2, but given the options and the definition of X, the factor of 1/2 accounts for double counting in binary collisions.

Multiple choice chemistry how far? how fast? collision theory collision theory of chemical reactions rate of chemical reaction

The number of collisions of Ar atoms with the walls of container per unit time?

  1. Increases when the temperature increases
  2. Remains the same when $CO _2$ is added to the container at constant temperature
  3. Increases when $CO _2$ is added to the container at constant temperature

  4. Decreases, when the average kinetic energy per molecule is decreased
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The number of collisions with the walls per unit time is proportional to the average speed of the molecules. Since average speed is proportional to the square root of temperature, increasing the temperature increases the collision frequency.

Multiple choice chemistry how far? how fast? collision theory collision theory of chemical reactions rate of chemical reaction

In a closed flask of $5$l $1.0$g $H _2$ is heated from $300$ to $600$K. Which statement is not correct?

  1. Pressure of the gas increases

  2. The rate of collisions increases

  3. The number of moles of gas increases

  4. The energy of gas molecules increases
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When 1.0g of H2 gas is heated in a closed flask, its temperature increases, which raises the pressure, the rate of molecular collisions, and the kinetic energy of the gas molecules. However, because the flask is closed, the total amount of gas remains constant, meaning the number of moles of gas does not change. Therefore, the statement that the number of moles increases is incorrect.

Multiple choice chemistry how far? how fast? collision theory collision theory of chemical reactions rate of chemical reaction

When the temperature of an ideal gas is increased at constant pressure?

  1. Collision number increases

  2. Collision frequency increases

  3. Mean free path increases

  4. Number of molecules per unit volume increases
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When temperature increases at constant pressure, the volume must increase (Charles's Law). The number of molecules per unit volume (N/V) decreases. The collision number (collisions per molecule) is related to the frequency of collisions, which depends on density and speed.

Multiple choice chemistry study of compounds a. hydrogen chloride laboratory method of preparation of hydrochloric acid physical and chemical properties and uses of hydrochloric acid hydrogen chloride: occurrence, preparation, purification and identification

Observing the method of collection of the gas, what you can tell about the density of hydrogen chloride?

  1. A gas that is more dense than air

  2. A gas that is less dense than air

  3. A gas (liqued form ) that is less dense than air

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A gas that is more dense than air can be collected by downward delivery. Examples of gases that can be collected by this method are carbon dioxide, chlorine, HCl, sulphur dioxide.