Which among the following statements about open, closed, and isolated systems is correct?
| 1. | The presence of reacting species in a covered beaker represents an open system. |
| 2. | In a closed system, there is an exchange of both energy and matter between the system and its surroundings. |
| 3. | A system containing reactants in a closed vessel made of copper is an example of a closed system. |
| 4. | A system containing reactants in a thermos flask or any other closed, insulated vessel is an example of a closed system. |
What happens to the specific heat of a gas when its volume is reduced to half of its initial value?
| 1. | Reduce to half | 2. | Be Doubled |
| 3. | Remain constant | 4. | Increase four times |
Calculate the correct values of heat transfer (q), change in temperature (ΔT), and work done (W) for the free expansion of an ideal gas under adiabatic conditions.
1. q = 0, ΔT ≠ 0, W = 0
2. q ≠ 0, ΔT = 0, W = 0
3. q = 0, ΔT = 0, W = 0
4. q = 0, ΔT = 0, W ≠ 0
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. | \( \mathrm{W} \text { (reversible) }=\mathrm{W} \text { (irreversible) }\) |
| 2. | \( \mathrm{W} \text { (reversible) }<\mathrm{W} \text { (irreversible) }\) |
| 3. | \( \mathrm{W} \text { (reversible) }>\mathrm{W} \text { (irreversible) }\) |
| 4. | \( \mathrm{W} \text { (reversible) }=\mathrm{W} \text { (irreversible) } + \text P_{\text {ext}}.\Delta V\) |
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 |
The enthalpies of elements in their standard states are taken as zero. The enthalpy of formation of a compound is :
| 1. | Generally negative | 2. | Always positive |
| 3. | Zero | 4. | Never negative |
Consider the following statement:
"A thermodynamic quantity is a state function"
The correct option is-
1. Used to determine heat changes
2. Whose value is independent of the path
3. Used to determine pressure-volume work
4. Whose value depends on temperature only.
What is a necessary condition for an adiabatic process to occur?
1. ∆T = 0
2. ∆P = 0
3. q = 0
4. w = 0