AP EAPCET (Engineering) Thermodynamics — practice questions
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Practice AP EAPCET (Engineering) Thermodynamics in the app →The first law of thermodynamics is mathematically expressed as:In an isothermal process for an ideal gas, which thermodynamic quantity remains constant?For an ideal gas expanding isothermally from volume $V_1$ to $V_2$ at temperature $T$, the work done by the gaFor an adiabatic process involving an ideal gas, which quantity is constant?Which of the following is an example of an **isolated** thermodynamic system?The mathematical statement of the **first law of thermodynamics** is:For the **isothermal free expansion** of an ideal gas into vacuum, which set of statements is correct?The first law of thermodynamics is essentially a statement of:Work done in an isothermal process for ideal gas:In an adiabatic process, the heat exchanged with surroundings is:The ratio Cp/Cv is denoted by:For an ideal gas, Cp − Cv equals:In an ISOCHORIC process, work done equals:For an adiabatic process on ideal gas: PV^γ = ?Internal energy change ΔU for an ideal gas depends ONLY on:In an isothermal expansion of ideal gas, the work done BY the gas is +500 J. The heat absorbed by the gas is:A monatomic ideal gas has γ = 5/3. For an adiabatic process, P₁V₁^γ = P₂V₂^γ. If V₂ = 8V₁, find P₂/P₁:1 mole of ideal gas (Cv = 3R/2) is heated at constant volume from 300 K to 600 K. Heat absorbed:For a monatomic ideal gas in isobaric expansion from V₁ to 3V₁, find ΔT/T₁:In a cyclic process, ΔU equals:The slope of an isothermal curve in PV diagram (dP/dV)_T equals:The slope of an adiabatic curve in PV diagram (dP/dV)_adiabatic equals:For a Carnot engine operating between T_h = 600 K and T_c = 300 K, efficiency is:A gas absorbs 500 J of heat and does 200 J of work. Change in internal energy:For a diatomic ideal gas (γ = 7/5), molar Cv equals:Isothermal bulk modulus of an ideal gas equals:Adiabatic bulk modulus of ideal gas equals:In a free expansion of ideal gas (into vacuum), the temperature:An ideal gas undergoes isobaric expansion. Q = 100 J, W = 40 J. Find ΔU:For an adiabatic process of an ideal gas, TV^(γ-1) = constant. If T₁ = 300 K and V₂ = 2V₁ for γ = 5/3, then T₂In a Carnot cycle, heat absorbed at hot reservoir is 1000 J. Efficiency 25%. Heat rejected at cold reservoir:For polytropic process PV^n = constant, n = 0 means:In which process is heat capacity infinite for ideal gas?A heat engine operates with 20% efficiency between two reservoirs. If T_h = 500 K, find T_c (for maximum/CarnoAn ideal gas undergoes isothermal expansion at 300 K from V = 1 to V = 2. Heat absorbed (n = 1):A diatomic ideal gas at 27°C is compressed adiabatically to ½ its volume. Find final temperature (γ = 7/5):Which law of thermodynamics leads to the concept of temperature?In which year was the zeroth law of thermodynamics formulated?Bodies A and B are each in thermal equilibrium with C. What follows for A and B?Two systems in thermal equilibrium must have equal values of which quantity?Before heat was understood as energy, it was pictured as an invisible fluid calledCount Rumford's 1798 cannon-boring observation supported which idea?Thermodynamics is best described as which kind of science?A bullet pierces a wooden block and stops. Its kinetic energy mainly becomesWhy is internal energy called a state variable?Which pair are NOT thermodynamic state variables?Heat flows on its own between two bodies in contact fromBetween two given states, which quantity is independent of the path taken?A gas expands by 2 x 10^-3 m^3 against a steady pressure of 10^5 Pa. Work done by the gas isWhat is the SI unit of specific heat capacity?Heat capacity per mole of a substance per kelvin is called itsBy equipartition of energy, the molar specific heat of a solid is aboutWhich solid is an exception to the 3R rule for molar heat at room temperature?The prediction C = 3R for solids fails mainly atOne calorie is the heat needed to warm 1 g of water fromAbout how much heat raises 100 g of water from 20 °C to 30 °C?An ideal gas has Cv = 20.8 J mol^-1 K^-1. Taking R = 8.31 J mol^-1 K^-1, Cp is aboutFor an ideal gas, Cv equals change in internal energy per kelvin per mole because U depends only onA relation connecting state variables such as PV = µRT is calledHow many independent state variables does a fixed amount of ideal gas have?A pressure-volume curve drawn at fixed temperature is calledA gas in equilibrium is split into two equal halves. Which quantity is halved in each part?Why can a gas during sudden free expansion into vacuum not be described by state variables?A quasi-static process is one that isIn a quasi-static process, the system and surroundings differ in pressure byA process in which the volume is kept constant is calledAn ideal gas expands isothermally and absorbs 600 J of heat. The work done by the gas isIn the adiabatic relation PV^γ = constant, γ stands forAn insulated gas does 150 J of work on a piston. The change in its internal energy isOne mole of ideal gas with γ = 1.4 cools by 20 K in adiabatic expansion. With R = 8.3 J mol^-1 K^-1, the work A gas in a rigid sealed tank absorbs 250 J of heat. The work done by the gas isIn an isobaric process of an ideal gas, the heat absorbed goes intoA gas completes a cycle and absorbs a net 80 J of heat. The net work done by it is'No process can have the sole result of turning heat from a reservoir fully into work' is theThe Clausius statement rules out a process whose only result isBy the second law, the coefficient of performance of a refrigerator can never beThe second law of thermodynamics says the efficiency of a heat engine can never beMost spontaneous processes in nature areWhich is a main cause of irreversibility in real processes?Which of these processes is reversible?The French engineer who first studied the maximum efficiency of a heat engine in 1824 wasThe Carnot cycle consists ofA Carnot engine has its source at 127 °C and sink at 27 °C. Its efficiency isA Carnot engine with sink at 300 K has 50% efficiency. Its source temperature isThe efficiency of a Carnot engine depends on theWhen every step of a Carnot cycle is run backwards, the device acts as aCarnot's theorem states that between two given temperatures no engine is more efficient thanAs temperature approaches absolute zero, the entropy of a system approachesThe constant entropy a system keeps at absolute zero is called itsWhich kind of solid can keep a residual entropy well above zero at absolute zero?A machine claimed to produce work with no energy input violates theIn a natural process, the total entropy of the interacting systemsAt absolute zero, a system is in the state of minimum thermal energy known as itsFor an isolated system, the first law implies that its total energyThe zeroth law makes thermal equilibrium a relation of which type?Which kind of thermodynamic system exchanges both energy and matter with its surroundings?Reactants kept in a sealed copper vessel form which type of system?Reactants sealed inside a thermos flask are an example of which system?What can a closed system exchange with its surroundings?A state function is a quantity whose value depends on:Which of these quantities is NOT a state function?A process with no heat transfer between system and surroundings is called:Joule found that a fixed amount of adiabatic work:Under the IUPAC sign convention, work done on a system is taken as:Using IUPAC signs, which equation states the first law of thermodynamics?The first law of thermodynamics says the energy of an isolated system:A process that runs infinitely slowly through a series of equilibrium states is:For isothermal reversible expansion of n mol of ideal gas, the work w equals:An ideal gas expands isothermally from 3 L to 8 L against a constant 2 atm. Heat absorbed?At constant volume, the heat absorbed by a system is equal to:Heat absorbed by a system at constant pressure measures the change in:The gap between ∆H and ∆U is usually negligible for a reaction involving:Which relation links ∆H and ∆U for a reaction of ideal gases?In ∆H = ∆U + ∆ngRT, the term ∆ng stands for:For N2(g) + 3H2(g) → 2NH3(g), what is the value of ∆ng?For H2(g) + Cl2(g) → 2HCl(g), how do ∆H and ∆U compare?A liquid has molar ∆vapH = 30.0 kJ/mol at 300 K. Treating the vapour as ideal, ∆vapU is about:The coefficient C in the relation q = C∆T is called the:A large heat capacity means a given heat input causes:How much heat raises 50 g of water by 10 °C if its specific heat is 4.18 J/g °C?