Chemistry Quiz Conducted By Dept Of Chemistry, Mrs. K.S.K. College, Beed

In an isochoric process, also known as a constant volume process, the volume remains constant. This means that there is no change in volume (dV = 0) during the process. Therefore, the correct answer is dV.

A well stoppered thermos flask prevents the exchange of heat and matter with the surroundings, making it an isolated system. The ice cubes inside the flask will not melt or transfer heat to the outside environment because of the insulation provided by the flask. Therefore, the thermos flask with ice cubes is an example of an isolated system where there is no exchange of energy or matter with the surroundings.

The statement "The total energy of an isolated system is constant" is the correct answer because according to the first law of thermodynamics, energy can neither be created nor destroyed in an isolated system. Therefore, the total energy remains constant.

In adiabatic expansion, the system undergoes expansion without any heat exchange with the surroundings. This means that no heat is added or removed from the system during the expansion process. As a result, the temperature of the system decreases. This is because the expansion causes the internal energy of the system to decrease, which in turn leads to a decrease in temperature. Therefore, the correct answer is adiabatic expansion.

Surface tension is an intensive property because it does not depend on the amount or size of the substance. It is a measure of the force required to stretch or break the surface of a liquid. Regardless of the quantity of liquid, the surface tension will remain the same. In contrast, mass and volume are extensive properties that depend on the amount of substance present, while enthalpy is also an extensive property that depends on the size or quantity of the system.

The intensive quantity is a physical property that does not depend on the amount of substance present. In this case, temperature and refractive index are the only options that fit this definition. Enthalpy and volume are extensive quantities that depend on the amount of substance, while temperature and refractive index are intensive quantities that remain constant regardless of the amount of substance.

During an isothermal expansion of an ideal gas, the temperature remains constant. Since both E (internal energy) and H (enthalpy) are directly proportional to temperature, and the temperature does not change in an isothermal process, both E and H will remain unaltered. This means that the internal energy and enthalpy of the gas will not increase or decrease during the expansion.

The given statement "It is an intensive property" is incorrect. Enthalpy is an extensive property, meaning it depends on the amount of substance present in the system. Intensive properties, on the other hand, are independent of the amount of substance and only depend on the state of the system.

In an isochoric process, the volume remains constant, so no work is done. Therefore, the increase in internal energy is equal to the heat absorbed, as there is no work done to contribute to the increase in energy.

The cooling in a refrigerator is due to the reaction of the refrigerator gas. When the gas in the refrigerator undergoes a chemical reaction, it absorbs heat from the surroundings, causing the temperature inside the refrigerator to decrease. This reaction is facilitated by the compressor, which compresses the gas, causing it to release heat. As a result, the gas cools down and is able to absorb more heat from the refrigerator, maintaining a low temperature inside.