Given the reaction:
\(2 \mathrm{Cl}(\mathrm{~g}) \rightarrow \mathrm{Cl}_2(\mathrm{~g})\)
What are the values of \(∆\mathrm{H}\) and \(∆\mathrm{S}\), respectively?
1. \(\Delta \mathrm{H}=0, \Delta \mathrm{~S}=-\mathrm{ve}\)
2. \(\Delta \mathrm{H}=0, \Delta \mathrm{~S}=0\)
3. \(\Delta \mathrm{H}=-\mathrm{ve}, \Delta \mathrm{~S}=-\mathrm{ve}\)
4. \(\Delta \mathrm{H}=+\mathrm{ve}, \Delta \mathrm{~S}=+\mathrm{ve}\)
For the reaction A + B → C + D + q (kJ/mol), entropy change is positive. The reaction will be
1. Possible only at high temperature
2. Possible only at low temperature
3. Not possible at any temperature
4. Possible at any temperature
The enthalpy of combustion of methane, graphite, and dihydrogen at 298 K are, –890.3 kJ mol–1 , –393.5 kJ mol–1, and –285.8 kJ mol–1 respectively. The enthalpy of formation of CH4(g) is-
1. | –74.8 kJ mol–1 | 2. | –52.27 kJ mol–1 |
3. | +74.8 kJ mol–1 | 4. | +52.26 kJ mol–1 |
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 |
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.
The entropy change can be calculated by using the expression . When water freezes in a glass beaker, the correct statement among the following is:
1. | ∆ S (system) decreases but ∆ S (surroundings) remains the same. |
2. | ∆ S (system) increases but ∆ S (surroundings) decreases. |
3. | ∆ S (system) decreases but ∆ S (surroundings) increases. |
4. | ∆ S (system) decreases but ∆ S (surroundings) also decreases. |
Based on the reactions, ascertain the valid algebraic relationship:
1. | x = y | 2. | x = 2y |
3. | x > y | 4. | x < y |