| (a) | Heat is a way of transferring energy. |
| (b) | Heat is not a property of the system, whereas temperature is a property of the system. |
| (c) | Reactions that are accompanied by the evolution of heat are called endothermic reactions. |
| (d) | Those reactions in which heat is absorbed are known as exothermic reactions. |
| Column-I | Column-II | ||
| (A) | Reversible process | (p) | \(\Delta G = -nFE\) |
| (B) | Gibbs free energy | (q) | Infinite steps |
| (C) | Standard enthalpy of reaction, \(\Delta_r H^{\ominus}\) | (r) | \(\sum\)bond enthalpies (reactants) – \(\sum\)bond enthalpies (products) |
| (D) | Enthalpy of bond formation, \(\Delta_f H_{\text {bond }}^{\ominus}\) | (s) | \(\sum \Delta_f H^{\ominus}\)(bonds of products) – \(\sum \Delta_f H^{\ominus}\)(bonds of reactants) |
| 1. | –65 kJ mol–1 | 2. | –75 kJ mol–1 |
| 3. | –50 kJ mol–1 | 4. | –80 kJ mol–1 |
| Column I (Reactions) | Column II (Enthalpy) | ||
| (A) | \(\small{CH_{4(g)} + 2O_{2(g)} \rightarrow CO_{2(g)} + 2H_2O}\) | (i) | \(\Delta _{sol}H^o\) |
| (B) | \( H_{2(g)} \rightarrow 2H_{(g)}\) | (ii) | \(\Delta _{lattice}H^o\) |
| (C) | \(NaCl_{(s)} \rightarrow Na^+_{(g)} + Cl^-_{(g)} \) | (iii) | \(\Delta _{c}H^o\) |
| (D) | \(NaCl_{(s)} \rightarrow Na^+_{(aq)} + Cl^-_{(aq)} \) | (iv) | \(\Delta _{bond}H^o\) |
The enthalpy change for the reaction is called
1. Enthalpy of formation
2. Enthalpy of vaporisation
3. Enthalpy of sublimation
4. Enthalpy of combustion
| 1. | 120.9 | 2. | 241.82 |
| 3. | 18 | 4. | 100 |
The enthalpy of vaporisation of a liquid is 30 kJ mol–1 and entropy of vaporisation is 75 J mol–1 k–1. What is the boiling point of the liquid at 1 atm?
| 1. | 50 K | 2. | 400 K |
| 3. | 450 K | 4. | 600 K |