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Right option is (a) ΔT = Q/C

Explanation: As we know that q = CΔT, where q is the heat energy, C is the specific heat and ΔT is the TEMPERATURE difference, When the temperature difference is expressed in TERMS of the heat capacity and heat energy, it is given as ΔT = q/C.

Correct option is (b) CP = DQ/dT

To elaborate: As we know that dq = CdT; where Q is the heat energy, C is the SPECIFIC heat and T is the temperature. At constant pressure, specific heat is given as CP. The specific heat at constant pressure is given by the expression CP = dq/dt.

Right answer is (c) 0

The best I can explain: When gas is expanded freely in a vacuum there is ZERO pressure exerted. The formula for WORK done is given by pressure X change in volume = 0 x 4. So the work done is zero in the process of FREE expansion.

Correct OPTION is (B) Universal gas constant

To elaborate: We all KNOW that ΔH = ΔU + nRΔT; ΔH = nCPΔT and ΔU = nCvΔT; ΔH – ΔU = nCPΔT – nCvΔT = n(CP – CV) ΔT. By equating L.H.S. and R.H.S., we get n(CP – CV) ΔT = nRΔT; CP – CV = R. Hence it’s PROVEN that difference of heat capacities at constant volume and pressure is the universal gas constant.

Correct answer is (a) 30

For explanation I WOULD say: We know that ΔH = ΔU + nRΔT; where ΔHis the enthalpy, ΔU is the internal energy, n is the number of moles, R is the UNIVERSAL gas CONSTANT and ΔT is the temperature DIFFERENCE. So enthalpy is 10 KJ + 20KJ = 30 KJ.

The correct answer is (b) Colour

To ELABORATE: An INTENSIVE property does not depend on the quantity or size of the object, whereas extensive property depends on the quantity and size of the object. Here VOLUME, enthalpy and INTERNAL ENERGY are extensive properties, while colour is an intensive property.

The correct CHOICE is (d) 20 NEWTON metre

To elaborate: The expression for work DONE is given by pressure x volume difference, here an ideal gas has a volume difference of 4 litres at 5 ATM pressure. So the work done = 10 – 6 litersx 5ATM = 20 Newton metre.

Right option is (a) True

Explanation: The EXPANSION of a gas in a VACUUM without PRESSURE is called free expansion. During the free expansion of gas, the work is not done WHETHER the process is reversible or Irreversible. So the above statement is considered to be true.

Right choice is (a) 30 Newton

Easy explanation: Force is defined as the product of pressure and the surface area so here as pressure is 3 atm and surface area is 10-metre SQUARE. The force that is APPLIED EQUALS 3 atm x 10-metre square = 30 Newton.

The CORRECT option is (c) 250 Newton metre

Best explanation: When a PRESSURE P is exerted through a volume V the work done is given by P ΔV, so here pressure is 5 atm and volume is a 50-metre cube. The work that is done is 5 atm X 50-metre cube = 250 Newton metre.

Right ANSWER is (a) INCREASES SLOWLY

To explain: Energy of a substance is directly PROPORTIONAL to its temperature. As we know that HEAT energy of a substance is q = mcΔT. If the temperature increases slowly then the energy also increases slowly.

The correct option is (b) ΔU = W

To explain: In an adiabatic process, the total energy is always zero. We have that ΔH = ΔU + W, as ΔH is zero, we get ΔU + W = 0; ΔU = -W. But as work is done on the SYSTEM by OBSERVING no heat W BECOMES NEGATIVE, so ΔU = -(-)W = W. Hence ΔU = W.

Correct option is (c) both mass and energy

The BEST explanation: An open system allows the TRANSFER of both mass and energy into the system from the surroundings. An example of an open system is the HUMAN BODY, we consume food, energy and excrete waste.

Correct option is (a) true

For explanation I would SAY: The FIRST LAW of thermodynamics is commonly stated as the law of conservation of energy that is energy can neither be created nor be destroyed, in other terms we can also say that the energy of an ISOLATED system is constant.

Right answer is (b) FALSE

The explanation: An OPEN system allows only energy transfer whereas an isolated system neither allows energy nor mass transfer through the system from the SURROUNDINGS. Isolated and CLOSED systems are not the same. So the above STATEMENT is false.

The correct choice is (B) PV^γ constant

Easy EXPLANATION: Let P is pressure and V is volume whereas Gamma is the ratio of specific HEAT capacity at constant pressure and volume. The relation between pressure and volume in an adiabatic process is GIVEN by PV^γ constant.

The correct option is (c) -50 KJ

To elaborate: The TOTAL energy in an adiabatic process is zero, so internal energy is equal to the NEGATIVE of the work DONE. Here work done is given by 50 kilojoules, so the internal energy is -50 kilojoules as the SUM of internal energy and the work done should be zero.

The CORRECT option is (a) adiabatic

Explanation: An adiabatic system does not allow the EXCHANGE of heat between system and surroundings. Energy is TRANSFERRED to the surrounding only through work Done. In the adiabatic process, the TOTAL energy is given as zero.

Correct option is (d) universal gas constant

Explanation: State functions are used to specify the state of a thermodynamic system. The state is described by measurable macroscopic particles like PRESSURE, TEMPERATURE, VOLUME, amount, etc and the is P, V and T are called state VARIABLES.

Correct answer is (b) internal energy

To explain: When a WORK is done or by the system, heat passes into out of the system and matter ENTERS or leaves the system, there is a change in internal energy of the system. It is REPRESENTED by the symbol “U”.