The specific heat of a substance my be broadly defined as the amount of heat required to raise the temperature of its unit mass through 1 degree. All the liquids and solids have one specific heat only. But a gas can have any number of specific heats depending upon the conditions, under which it is heated.
Specific heat at constant volume is the amount of heat required to raise the temperature of a unit mass of a gas throught 1 degree, when it is heat at constant volume.
Specific heat at constant pressure is the amount of heat required to raise the temperature of a unit mass of a gas through 1 degree, when it is heated at constant pressure.
The ratio of specific heat at constant pressure Cp and specific heat at constant volume Cv is always more than one.
4) The amount of heat required to raise the temperature of the unit mass of gas through one degree at constant volume, is called
specific heat at constant volume
Related Thermodynamics MCQ with Answers
Right
An irreversible process is a process that cannot return both the system and the surroundings to their original conditions. That is, the system and the surroundings would not return to their original conditions if the process was reversed. There is a loss of heat in an irreversible process.
For example, an automobile engine does not give back the fuel it took to drive up a hill as it coasts back down the hill. There are many factors that make a process irreversible. Four of the most common causes of irreversibility are friction, unrestrained expansion of a fluid, heat transfer through a finite temperature difference, and mixing of two different substances. These factors are present in real,irreversible processes and prevent these processes from being reversible.
all of the above
Adiabatic process or Isentropic process:
A process, in which the work substance neither receives nor gives out heat to its surroundings, during its expansion or compression is called an adiabatic process. This will happen when the working substance remains thermally insulated, so that no heat enters or leaves it during the process. It is thus obvious, that in an adiabatic process no heat leaves or enters the gas, the temperature of the gas changes, as the work is done at the cost of internal energy and the change in internal energy is equal to the work done.
An adiabatic process is one in which
* No heat enters or leaves the gas
* The temperature of the gas changes
* The change in internal energy is equal to the mechanical work done
Incorrect
Water gas, colorless poisonous gas that burns with an intensely hot, bluish (nearly colorless) flame. The gas is a mixture of carbon monoxide and hydrogen with very small amounts of other gases, e.g. , carbon dioxide, and is almost entirely combustible as a result. Water gas is so named because of the use of water (steam) in its preparation. This process involves treating white-hot hard coal or coke with a blast of steam; carbon monoxide and hydrogen are formed. The gas is manufactured in vast quantities for commercial use. It is of much importance in the preparation of hydrogen and as a fuel in the making of steel and in other industrial processes.
Right
When the gas is heated at constant volume, the heat supplied increases the internal energy of the gas.
