NEET UG Thermodynamics — practice questions
93 free MCQs with worked solutions. Tap any question for the answer + explanation, or practice them all in the app.
Practice NEET UG Thermodynamics in the app →Per NCERT §5.1.2, an OPEN system exchanges what with its surroundings, in contrast to a closed or isolated onePer NCERT §5.1.2, an ISOLATED system is exemplified by which container?Per NCERT §5.1.4, the INTERNAL ENERGY U of a system is classified as which kind of property?Per NCERT eqn 5.1, the FIRST LAW of thermodynamics is expressed as which equation, with sign conventions?Per NCERT eqn 5.2, the pressure-volume WORK done on a gas at constant external pressure p_ex is given by whichPer NCERT §5.2.1 + eqn 5.5, for an isothermal REVERSIBLE expansion of n mol of an ideal gas from V_i to V_f, wPer NCERT §5.2.1 (free expansion), what is the work done in FREE EXPANSION of an ideal gas into vacuum (p_ex =Per NCERT §5.2.1, a process is called REVERSIBLE if it satisfies which condition?Per NCERT §5.2.1, for an ADIABATIC process (no heat exchange, q = 0), the first law reduces to which form?Per NCERT §5.2.1, for an ISOTHERMAL IRREVERSIBLE expansion of an ideal gas at constant external pressure p_ex,Per NCERT §5.2.1, at CONSTANT VOLUME (ΔV = 0), the first law simplifies to which?Per NCERT Problem 5.2, when 2 L of an ideal gas at 10 atm expands isothermally into VACUUM to total volume 10 Per NCERT §5.2.2 + eqn 5.7, the ENTHALPY H is defined as which quantity?Per NCERT eqn 5.10, the relationship between ΔH and ΔU for a gaseous reaction is which?Per NCERT Problem 5.5, for vaporisation of 1 mol of water at 100 °C and 1 bar, given ΔH = 41 kJ/mol, what is ΔPer NCERT eqn 5.13, the relationship between C_p and C_v for an ideal gas is which?Per NCERT §5.4(a), the STANDARD STATE of a substance at a specified temperature is which?Per NCERT Table 5.1, the standard enthalpies of fusion and vaporisation of WATER are which?Per NCERT §5.4(c), what is the CONVENTION for the standard enthalpy of formation Δ_f H° of an ELEMENT in its rPer NCERT Table 5.2, Δ_f H° of methane CH₄(g) is which value?Per NCERT eqn 5.15, the standard enthalpy of REACTION from formation enthalpies is computed as which?Per NCERT §5.4(e), HESS'S LAW of constant heat summation states which?Per NCERT §5.4(e) (worked example), given C+O₂→CO₂ ΔH = −393.5 and CO+½O₂→CO₂ ΔH = −283.0 kJ/mol, what is Δ_f Per NCERT §5.4(d) (thermochemical equations), if a chemical equation is REVERSED, what happens to Δ_r H°?Per NCERT §5.5(a), the STANDARD ENTHALPY OF COMBUSTION Δ_c H° of butane (cooking gas) is which?Per NCERT §5.5(a), the standard enthalpy of combustion of GLUCOSE (C₆H₁₂O₆) is which?Per NCERT §5.5(b), the ENTHALPY OF ATOMIZATION Δ_a H° of dihydrogen is which value, and how does it relate to Per NCERT §5.5(c), in CH₄ atomisation requires 1665 kJ/mol. What is the MEAN C-H bond enthalpy?Per NCERT eqn 5.17, the standard enthalpy of a GAS-phase reaction from bond enthalpies is approximated as whicPer NCERT Table 5.3(b), the bond enthalpy of N≡N triple bond is which value — among the highest known for diatPer NCERT §5.5(d), the LATTICE ENTHALPY of an ionic compound is defined as the enthalpy change for which procePer NCERT §5.5(d), the BORN-HABER cycle for NaCl uses Hess's law and includes which steps?Per NCERT §5.5(e), the enthalpy of SOLUTION Δ_sol H° of an ionic compound in water is decomposed as which sum?Per NCERT §5.3, a BOMB CALORIMETER measures which thermodynamic quantity?Per NCERT Problem 5.6, 1 g graphite burnt in a bomb calorimeter (heat capacity 20.7 kJ/K) raises temperature bPer NCERT Table 5.2, the Δ_f H° of C(diamond) is which value (note: NOT zero, because graphite — not diamond —Per NCERT §5.6, a SPONTANEOUS process is best defined as which of the following?Per NCERT §5.6(b), ENTROPY S is best described as which?Per NCERT eqn 5.18, the entropy change for a REVERSIBLE process is given by which expression?Per NCERT eqn 5.19, for a SPONTANEOUS process the TOTAL entropy change (system + surroundings) obeys which inePer NCERT Problem 5.10, in which of the following processes does entropy DECREASE?Per NCERT §5.6(e), the THIRD LAW of thermodynamics states which?Per NCERT §5.6(d), the SECOND LAW of thermodynamics, in entropy form, states which?Per NCERT eqn 5.20-21, GIBBS energy G and its change ΔG at constant T are given by which expressions?Per NCERT §5.6(c) (criteria), the sign of ΔG for a SPONTANEOUS process at constant T and p is which?Per NCERT Table 5.4, a reaction with ΔH < 0 AND ΔS > 0 is spontaneous under which condition?Per NCERT Table 5.4, a reaction with ΔH > 0 AND ΔS > 0 is spontaneous under which condition?Per NCERT §5.7 eqn 5.23, the relation between ΔG° and equilibrium constant K is which?A gas absorbs $200$ J of heat and does $80$ J of work on its surroundings. The change in internal energy is:A pump compresses gas very fast, so no heat escapes. The process is:A Carnot engine works between $T_h = 400$ K and $T_c = 300$ K. Its efficiency is:A glass of cold lassi placed on a kitchen counter eventually warms to room temperature. The second law of therFor a reaction occurring at constant pressure in an open beaker, the heat absorbed equals:Hess's law states that the standard enthalpy change for a reaction:Among solid ice, liquid water, and water vapour at the same temperature, entropy is:A reaction has $\Delta H = -100$ kJ and $\Delta S = +200$ J/K. At $T = 298$ K, $\Delta G$ is:Two systems in thermal contact eventually reach the same temperature. This empirical fact is the basis of the:The first law of thermodynamics is a statement of:Internal energy of an ideal gas depends only on:In an isothermal process for an ideal gas:In an adiabatic process:For an ideal gas undergoing an isothermal process from V₁ to V₂, the work done by the gas is:The relation between Cp and Cv for an ideal gas (per mole) is:An ideal gas at temperature T₁ is expanded adiabatically. Its final temperature T₂ is:The Carnot engine's efficiency between source temperature T₁ (hot) and sink T₂ (cold) is:The second law of thermodynamics can be stated as: no engine can convert into work:The change in internal energy of an ideal gas (γ = 1.4) when 2 moles are heated from 300 K to 400 K at constanA Carnot engine operates between 400 K and 300 K. If it absorbs 800 J from the hot reservoir per cycle, the woFor an ideal gas the adiabatic equation linking pressure and volume is:A refrigerator extracts 600 J from the cold compartment and rejects 800 J to the room. Its coefficient of perfWhich of the following is a reversible process in the thermodynamic sense?Two systems each in thermal equilibrium with a third are in equilibrium:The law about equilibrium with a third system is the:The zeroth law was formulated by:The zeroth law was formulated in the year:The quantity equal for two systems in thermal equilibrium is:A wall that does not let heat pass is called:Which of these is a thermodynamic variable?In an isothermal process the quantity held fixed is the:For an ideal gas in an isothermal process, PV stays:Gas expanding in a cylinder inside a large fixed temperature reservoir is:In an isothermal expansion, the heat supplied equals the:A device converting heat to work through a cyclic process is a:The Kelvin-Planck statement rules out converting heat completely into:The Clausius statement forbids heat flowing on its own from a body:The Kelvin-Planck and Clausius statements are:Rudolf Clausius is regarded as the discoverer of which law?Rudolf Clausius was born in:The entropy of an isolated system can never:Besides thermodynamics, Clausius worked on the kinetic theory of:A heat engine takes its working substance around a process that is:A perfect refrigerator is denied by the statement due to:Clausius arrived at the second law building on the work of Carnot and: