Test: Entropy & Gibbs Energy - NEET MCQ

As the randomness increases on evaporation, entropy also increases. 
The greater the randomness in a system, greater is its entropy.

The second law of thermodynamics states that for any spontaneous process, the overall ΔS must be greater than or equal to zero.

The greater the randomness in a system, greater is its entropy. The randomness is greater in liquid state as compared to solid state so the entropy increases when ice melts into water.

+ve (because gases are highly random than liquid) ΔS = S(g) - S(l) = +ve

Intensive properties: Properties which are independent of the amount of substance (or substances) present in the system are called intensive properties, e.g. pressure, density, temperature, viscosity, surface tension, refractive index, emf, chemical potential, sp. heat etc, These are intensive properties.
So, we can say that entropy is an extensive property.

In cases where ΔG is: negative, the process is spontaneous and proceed in the forward direction.

The sign of ΔG will change from positive to negative (or vice versa) where T = ΔH/ΔS. In cases where ΔG is: negative, the process is spontaneous and may proceed in the forward direction as written. positive, the process is non-spontaneous as written, but it may proceed spontaneously in the reverse direction.

Evaporation of water from an open pot is a spontaneous process. As it starts on its own without any external agent. However it takes heat from surrounding means that it is endothermic.

A state function is the property of the system whose value depends only on the initial and final state of the system and is independent of the path. It is a state function because it is independent of the path. Heat (q) and work (W) are not state functions being path dependent.

The value of equilibrium constant(k) = 10
∆G^θ = -2.303RTlogk
Δ G^θ for the reaction,
= (2.303)(8.314JK⁻¹mol⁻¹)(300K)log10 = –5744.14 Jmol⁻¹ = –5.744 kJ mol⁻¹