Chemistry Question Bank

H and E  for the reaction, Fe O s 3H g 2Fe s H O l → at constant temperature are related as (a) H E (b) H E RT (c) H E RT (d) H E 3RT

The enthalpy of vaporisation of a compound AB at its boiling point (127°C) is 6.4 kJ mol-1. Its entropy of vaporization is

The densities of graphite and diamond at 298 K are 2.25 and 3.31 g cm–3, respectively. If the standard free energy difference is equal to 1895 J mol–1, the pressure at which graphite will be transformed into diamond a…

For the reaction, 2H O g 2H g O g → ∆H = 571.6 KJ fH of water is :

The heat of formation of Fe O s is –824.2 kJ mol–1. ∆H for the reaction. 2Fe O s 4Fe s 3O g → is:

105. (∆U – ∆H) for the formation of NH₃ from N₂ and H₂ is :

The standard enthalpies of formation of HCl(g), H  (g) and  Cl₂(g)  are  –92.2,  217.7  and  121.4  kJ  mol-1 respectively. The bond dissociation energy of HCl is:

For the reaction, 8 g 2 g 2 g l C H 5O 3CO 4H O → at constant temperature, H E is (2003)

Assume each reaction is carried out in an open container. For which reaction will H = E ? (CBSE AIPMT 2006) (a) H (g) Br (g) 2HBr(g) → (b) C(s) 2H O(g) 2H (g) CO (g) → (c) PCl (g) PCl (g) Cl (g) → (d) 2CO(g) O (g) 2CO…

Identify the correct statement for change of Gibbs’ energy for a system system ( G ) at constant temperature and pressure. (2006)

Consider the following reaction –1 (aq) (aq) (l) –1 2(g) 2(g) (l) 2(g) 2(g) (g) (l) –1 2(g) 2(g) 2(g) (l) –1 (i)H OH H O , H X kJ mol (ii)H 1/ 2O H O , H X kJ mol (iii)CO H CO H O , H X kJ mol (iv)C H 5 / 2O 2CO H O ,…

Given that bond energies of H – H and Cl – Cl are 430 kJ mol–1 and 240 kJ mol–1 respectively and f H for HCl is-90 kJ mol–1 bond enthalpy of HCl is (2007)

From the following bond energies: H — H bond energy : 431.37 kJ mol–1 C == C bond energy : 606.10 kJ mol–1 C — C bond energy : 336.49 kJ mol–1 C — H bond energy : 410.50 kJ mol–1 Enthalpy for the reaction, will be (2009)

Which of the following are not state functins? (I) q + w (II) Q (III) w (IV) H – TS (2009)

The heat liberated when 1.89 g of benzoic acid is burnt in a bomb calorimeter at 25 °C increases the temperature of 18.94 kg of water by 0.632 °C. If the specific heat of water at 25 °C is 0.998 cal/g-deg, the value o…

The following two reactions are known Fe₂O₃(s) + 3CO(g) → 2Fe(s) + 3CO₂(g); ∆H = –26.8 kJ FeO(s) + CO(g) → Fe(s) + CO₂(g); ∆H = – 16.5 kJ The value of ∆H for the following reaction Fe₂O₃(s) + CO(g) → 2FeO(s) + CO₂(g) …

Three thermochemical equations are given below: (i) C(graphite) + O₂(g) → CO₂(g); ∆rH° = x kJ mol–1 (ii) C(graphite) + ½O₂(g) → CO(g); ∆rH° = y kJ mol–1 (iii) CO(g) + ½O₂(g) → CO₂(g); ∆rH° = z kJ mol–1 Based on the ab…

When 5 litres of a gas mixture of methane and propane is perfectly combusted at 0°C and 1 atmosphere, 16 litres of oxygen at the same temperature and pressure is consumed. The amount of heat released from this combust…

The heat of combustion of carbon to CO₂ is –393.5 kJ/mol. The heat released upon formation of 35.2 g of CO₂ from carbon and oxygen gas is (2015)

For a sample of perfect gas when its pressure is changed isothermally from pi to pf, the entropy change is given by. (NEET-II 2016)

For a given reaction, ∆H = 35.5 kJ mol–1 and ∆S = 83.6 J K–1 mol–1. The reaction is spontaneous at (Assume that ∆H and ∆S do not vary with temperature.) (NEET 2017)

The bond dissociation energies of X2, Y₂ and XY are in the ratio of 1 : 0.5 : 1. ∆H for the formation of XY is – 200 kJ mol–1. The bond dissociation energy of X2 will be (NEET 2018)

An ideal gas expands isothermally from 10–3 m3 to 10–2 m3 at 300 K against a constant pressure of 105 N m–2. The work done on the gas is (Odisha NEET 2019)

In which case change in entropy is negative? (NEET 2019)

Match List I with List II and select the correct answer using the codes given below the lists: List – I List – II A. T G P