Chemistry Question Bank

The values of H and S for the reaction, (graphite) 2(g) (g) C CO 2CO → Are 170 kJ and 170 JK–1, respectively. This reaction will be spontaneous at (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…

Enthalpy change for the reaction, 4H(g) 2H (g) → is – 869.6 kJ. The dissociation energy of H–H bond is (CBSE AIPMT 2011)

If the enthalpy change for the transition of liquid water to steam is 30 kJ mol–1 at 27°C, the entropy change for the process would be (2011)

Standard enthalpy of vaporisation o vap H for water at 100°C is 40.66 kJ mol–1. The internal energy of vaporisation of water at 100°C (in kJ mol–1) is (2012)

In which of the following reactions, standard reaction entropy change (∆S°) is positive and standard Gibbs energy change (∆G°) decreases sharply with increasing temperature? (2012)

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…

For the reaction, X2O₄(l) → 2XO₂(g) ∆U = 2.1 kcal, ∆S = 20 cal K–1 at 300 K Hence, ∆G is (2014)

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)

Consider the following liquid-vapour equilibrium. Liquid ⇌ Vapour Which of the following relations is correct? (NEET-I 2016) (a) v H dln P dT T (b) v H d ln P dT RT (c) v H dln G dT RT (d) v H d ln P dT RT

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)

Which thermodynamic parameter is not a state function?

A system undergoes a 3-step process. In step 1, 25 J of work is done by the system as its internal energy (U) decreases by 50 J. In step 2, w = -15J and q = +40J. In step 3 at constant volume, the system gives off 50 …

A liquid which is confined inside an adiabatic piston is suddenly taken from state 1 to state 2 by a single stage process. If the piston comes to rest at point 2 as shown. Then the enthalpy change for the process will…

A diatomic gas at pressure P, compressed adiabatically to half of its volume, what is the final pressure?

The magnitudes of enthalpy changes for irreversible adiabatic expansion of a gas from 1L to 2L is H₁ and for reversible adiabatic expansion for the same expansion is H₂. Then

For the reaction of one mole of zinc dust with one mole of sulphuric acid in a bomb calorimeter, U and w correspond to

In an isobaric process, when temperature changes from 1T to T , S is equal to

For which of the following cases H S T ?

Bond dissociation energy of CH₄ is 360 kJ/mol and C₂H₆ is 620 kJ/mol. Then bond dissociation energy of C – C bond is

Assertion: The extensive properties of a single pure substance will not only depend upon the number of moles of the substance present but also on any two of the three variables. Reason: Any extensive property if expre…

Assertion: For an isolated system, q is zero. Reason: In an isolated system, change in U and V is zero.

Assertion: Addition of Q and w gives ΔU. Reason: Addition of two path functions cannot give state function.

Which of the following macroscopic variable is not measurable?