Thermodynamics - Online Test

Q1. Thermodynamics is the branch of physical science concerned with
Explaination / Solution:

Thermodynamics deals with heat and its transformation from one form to another. The branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.

Q2. In a closed system, Which of the following take place ?
Explaination / Solution:

In a closed system, there is no flow of matter from system to surrounding or vice versa. For example, a certain quantity of fluid bounded within a closed cylinder constitutes a closed system.

Q3. In an open system, which if the following take place ?
Explaination / Solution:

In open system there is flow of matter and energy in and out of the system or vice versa. For example, an air compressor in which the air enters at a low pressure and exit at high pressure and there is energy interaction with the surrounding

Q4. first law of thermodynamics is a restatement of
Explaination / Solution:

t is restatement of law of conservation of energy. It states that Thermodynamics isthe branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.

Q5. According to first law of thermodynamics ΔU = q + w, where
Explaination / Solution:

In thermodynamics q=+ve when heat is supplied to the system. And w=+ve when work is done on the system while when work is done by the system w is taken as –ve.

Q6. If  is the final volume and  is the initial volume and  the external pressure the work done can be calculated by
Explaination / Solution:

ViVfpexdV
Q7. For isothermal reversible free expansion of an ideal gas from  the initial volume to  the final volume the work done on the gas is
Explaination / Solution:

this is workdone by the system in iosothermal process.
Q8. The correct equation for change in enthalpy is:
Explaination / Solution:

Enthalpy is a thermodynamic quantity equivalent to the total heat content of a system. It is equal to the internal energy of the system plus the product of pressure and volume.

Q9. The molar heat capacity of a substance is the
Explaination / Solution:

The molar heat capacity of a substance is the quantity of heat needed to raise the temperature of one mole by one degree Celsius.

Q10. The relationship between  and CV for an ideal gas is
Explaination / Solution:

For ideal gas Cp- CV = nR. For1 mole of gas n=1.