Advertisements
Advertisements
प्रश्न
What are spontaneous reactions?
उत्तर
A reaction that occurs under the given set of conditions without any external driving force is called a spontaneous reaction.
APPEARS IN
संबंधित प्रश्न
∆S is expected to be maximum for the reaction
What is the usual definition of entropy?
What is the unit of entropy?
Identify the state and path functions out of the following:
- Enthalpy
- Entropy
- Heat
- Temperature
- Work
- Free energy
State the various statements of the second law of thermodynamics.
1 mole of an ideal gas, maintained at 4.1 atm and at a certain temperature, absorbs heat 3710 J and expands to 2 litres. Calculate the entropy change in the expansion process.
30.4 kJ is required to melt one mole of sodium chloride. The entropy change during melting is 28.4 JK−1 mol−1. Calculate the melting point of sodium chloride.
You are given normal boiling points and standard enthalpies of vapourisation. Calculate the entropy of vapourisation of liquids listed below.
| Liquid | Boiling points (°C) | ΔH (kJ mol−1) |
| Ethanol | 78.4 | + 42.4 |
Cyanamide (NH2CN) is completely burnt in excess oxygen in a bomb calorimeter, ΔU was found to be −742.4 kJ mol−1, calculate the enthalpy change of the reaction at 298 K.\[\ce{NH2CN_{(s)} + 3/2 O2_{(g)} -> N2_{(g)} + CO2_{(g)} + H2O_{(l)}}\] ΔH = ?
For the reaction at 298 K: \[\ce{2A + B -> C}\]
ΔH = 400 KJ mol−1; ΔS = 0.2 KJ K−1 mol−1 Determine the temperature at which the reaction would be spontaneous.
