When compared to ΔG° for the formation of Al₂O₃, the ΔG° for the formation of Cr₂O₃ is

• higher

• lower

• same

• unpredicted

Consider the Born-Haber cycle for the formation of an ionic compound given below and identify the compound (Z) formed.

• M⁺X^-

• M⁺X^-(s)

• MX

• M⁺X^-(g)

For the reaction H₂O (l) $\rightleftharpoons$ H₂O (g) at 373 K and 1 atm pressure

• $∆$H = 0

• $∆$E = 0

• $∆\mathrm{H} = \mathrm{T}∆\mathrm{S}$

• $∆\mathrm{H} = ∆\mathrm{E}$

The enthalpy of formation of NH₃ is - 46kJ mol^-1. The enthalpy change for the reaction is-

2NH₃ (g) → N₂ (g) + 3H₂ (g) 

• +184 kJ

• +23 kJ

• +92 kJ

• +46 kJ

Enthalpy of vaporization of benzene is + 35.3 kJ mol^-1at its boiling point, 80C. The entropy change in the transition of the vapour to liquid at its boiling point in [JK^-1mol^-1] is

• -441

• -100

• +441

• +100

The amount of heat evolved when 500 cm³ of 0.1 M HCl is mixed with 200 cm³ of 0.2 M NaOH is

• 2.292 kJ

• 1.292 kJ

• 0.292 kJ

• 3.392 kJ

During the adsorption of krypton on activated charcoal at low temperature.

• ΔH > 0 and ΔS < 0

• ΔH < 0 and ΔS < 0

• ΔH > 0 and ΔS > 0

• ΔH < 0 and ΔS < 0

The amount of heat evolved when 500 cm³ of 0.1 M HCl is mixed with 200 cm³ of 0.2 M NaOH is

• 2.292 kJ

• 1.292 kJ

• 22.9 kJ

• 0.292 kJ

509.

The enthalpy of vaporization of benzene is +35.3 kJ/mol at its boiling point, 80°C. The entropy change in the transition of vapour to liquid at its boiling point is

• -100

• +100

• +342

• -342

Based on the first law of thermodynamics, which one of the following is correct?

• For an isothermal process, Q = + W

• For an isochoric process, $∆$U = -Q

• For an adiabatic process, $∆$U= -W

• For a cyclic process, Q = -W