Assertion (A): | Combustion of all organic compounds is an exothermic reaction. |
Reason (R): | The enthalpies of all elements in their standard state are zero. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Assertion (A): | Spontaneous process is an irreversible process and may be reversed by some external agency. |
Reason (R): | A decrease in enthalpy is a contributing factor to spontaneity. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Assertion (A): | A liquid crystallizes into a solid and is accompanied by a decrease in entropy. |
Reason (R): | In crystals, molecules organize in an ordered manner. |
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | (A) is False but (R) is True. |
Thermodynamics is not concerned about:
1. | Energy changes involved in a chemical reaction. |
2. | The extent to which a chemical reaction proceeds. |
3. | The rate at which a reaction proceeds. |
4. | The feasibility of a chemical reaction. |
The correct statement among the following is:
1. | The presence of reacting species in a covered beaker is an example of an open system. |
2. | There is an exchange of energy as well as matter between the system and the surroundings in a closed system. |
3. | The presence of reactants in a closed vessel made up of copper is an example of a closed system. |
4. | The presence of reactants in a thermos flask or any other closed insulated vessel is an example of a closed system. |
If the volume of a gas is reduced to half from its original volume, then the specific heat will:
1. | Reduce to half | 2. | Be Doubled |
3. | Remain constant | 4. | Increase four times |
During the complete combustion of one mole of butane, 2658 kJ of heat is released. The thermochemical reaction for this change is:
1. | |
2. | |
3. | |
4. |
of formation of at certain temperature is . The value of is-
1. Zero
2.
3.
4. Equal to
In an adiabatic process, no transfer of heat takes place between the system and its surroundings. The correct option for free expansion of an ideal gas under adiabatic condition from the following is:
1.
2.
3.
4.
The pressure-volume work for an ideal gas can be calculated by using the expression .
The work can also be calculated from the pV-plot by using the area under the curve within the specified limits.
An ideal gas is compressed (a) reversibly or (b) irreversibly from volume to .
The correct option is:
1.
2.
3.
4.