19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
A thermally isolated gaseous system can exchange energy with the surroundings. The mode of energy may be
Gaseous system is placed with pressure P₁, volume V₁ and temperature T1, it has undergone thermodynamic changes where temperature is remaining constant, it is
Based on the first law of thermodynamics, which one of the following is correct?
U q w , is mathematical expression for
According to the first law of thermodynamics, U q w . In special cases the statement can be expressed in different ways. Which of the following is not a correct expression?
Two moles of Helium gas undergo a reversible cyclic process as shown in figure. Assuming gas to be ideal. What is the work done for the process C to D?
E is always positive, when
An ideal gas is taken around the cycle ABCA as shown in P-V diagram The net work done by the gas during the cycle is equal to:
An ideal gas receives 10 J of heat in a reversible isothermal expansion. Then the work done by the gas:
One mole of an ideal gas is initially at 0°C and 1 atm pressure. If it absorbs 1000 cal heat during a reversible isothermal expansion, what will be its final volume?
The maximum work obtained by an isothermal reversible expansion of 1 mole of an ideal gas at 27°C from 2.24 to 22.4 L is (R = 2 cal)
16g of oxygen gas expands isothermally and reversibly at 300 K from 10 dm3 to 100 dm3. The work done is (in J)
The work done during the expansion of a gas from a volume of 4dm3 to 6 dm3 against a constant external pressure of 3 atm is
1 mole of NH₃ gas at 27°C is expanded in reversible adiabatic condition to make volume 8 times (γ = 1.33). Final temperature and work done by the gas respectively are:
One mole of an ideal gas expands reversibly and adiabatically from a temperature of 27°C. If the work done during the process is 3 kJ, then final temperature of the gas is:(CV = 20 J/K)
Which of the following expressions regarding entropy is not correct? (a) system q S T (b) system total surrounding S S S (c) final initial S S S (d) total system surrounding S S S
Read the following statements regarding spontaneity of a process and mark the appropriate choice. (i) When enthalpy factor is absent then randomness factor decides spontaneity of a process. (ii) When randomness fact…
Unit of entropy is
In which case change in entropy is negative?
When one mole of an ideal gas is compressed to half of its initial volume and simultaneously heated to twice its initial temperature, the change in entropy of gas (∆S) is :
One mole of an ideal diatomic gas (Cv = 5 cal) was transformed from initial 25°C and 1 L to the state when temperature is 100°C and volume 10 L. The entropy change of the process can be expressed as (R = 2 calories/mo…
Pick out the wrong statement
Which one of the following is correct? (a) G H T S
G is the net energy available to do useful work and is a measure of free energy. If a reaction has positive enthalpy change and positive entropy change, under what conditions will the reaction be spontaneous?
Which of the following processes is reversible?