Practice free Chemical Thermodynamics (Chemistry) NEET multiple-choice questions online with instant answers and detailed explanations. No login required.
If ΔH is the change in enthalpy and ΔE the change in internal energy accompanying a gaseous reaction [KCET 1989; CBSE PMT 1990]
If Δn = –ve than ΔH < ΔE.
Enthalpy for the reaction C + O2 → CO2 is [DPMT 1987, 91]
It is a combustion reaction, ΔH = –ve.
The work done in ergs for the reversible expansion of one mole of an ideal gas from a volume of 10 litres to 20 litres at 25°C is
.
In a reversible isothermal process, the change in internal energy is
ΔE = 0 for reversible isothermal process.
The enthalpy of neutralization of which of the following acids and bases is nearly –13.6 Kcal [Roorkee 1999]
Heat of neutralisation of a strong acid and strong base is equal to –13.7 kcal.
Work done during isothermal expansion of one mole of an ideal gas from 10 atm to 1 atm at 300 K is (Gas constant = 2) [AIIMS 2000]
log
log
Joule-Thomson expansion is [JIPMER 2000]
Joule-Thomson expansion is isoenthalpic.
n thermodynamics, the Joule–Thomson effect (also known as the Joule–Kelvin effect, Kelvin–Joule effect) describes the temperature change of a real gas or liquid (as differentiated from an ideal gas) when it is forced through a valve or porous plug while keeping it insulated so that no heat is exchanged with the environment.[1][2][3]This procedure is called a throttling process or Joule–Thomson process.[4] At room temperature, all gases except hydrogen, helium and neon cool upon expansion by the Joule–Thomson process when being throttled through an orifice; these three gases experience the same effect but only at lower temperatures.[5][6] Most liquids such as hydraulic oils will be warmed by the Joule-Thomson throttling process.
The gas-cooling throttling process is commonly exploited in refrigeration processes such as air conditioners, heat pumps, and liquefiers.[7][8] In hydraulics, the warming effect from Joule-Thomson throttling can be used to find internally leaking valves as these will produce heat which can be detected by thermocouple or thermal-imaging camera. Throttling is a fundamentally irreversible process. The throttling due to the flow resistance in supply lines, heat exchangers, regenerators, and other components of (thermal) machines is a source of losses that limits the performance.
In an adiabatic expansion of an ideal gas [KCET (Med.) 2001; MH CET 2000]
q = ΔE – W, if q = 0 for adiabatic process, than ΔE = W.
For the reaction at 25°C and 1 atm. pressure, ΔH = –874 kJ. Then the change in internal energy (ΔE) is …. [Orissa JEE 2002]
For this reaction Δn = 0 than ΔE = ΔH.
One mole of an ideal gas is allowed to expand freely and adiabatically into vacuum until its volume has doubled. A statement which is not true concerning this expression is [Pb. PMT 1998]
ΔS = 0 is not true.
Ready to ace NEET?
Free access · No credit card required
Yes. You can attempt every Chemical Thermodynamics question on this page for free without logging in, and check the correct answer with a detailed explanation instantly.
No account is required to attempt questions and view answers. A free account adds bookmarks, personal notes, and progress tracking.
The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.