List of top Chemistry Questions on Spontaneity

Match the following. \[ \begin{array}{|c|c|} \hline \textbf{List-I} & \textbf{List-II} \\ \hline \begin{array}{l} \textbf{A.}\; \Delta_rH<0,\; \Delta_rS>0,\; \Delta_rG<0 \\ \textbf{B.}\; \Delta_rH<0,\; \Delta_rS<0,\; \Delta_rG<0 \\ \textbf{C.}\; \Delta_rH>0,\; \Delta_rS>0,\; \Delta_rG>0 \\ \textbf{D.}\; \Delta_rH>0,\; \Delta_rS<0,\; \Delta_rG>0 \end{array} & \begin{array}{l} \textbf{I.}\; \text{Non-spontaneous at low temperature} \\ \textbf{II.}\; \text{Spontaneous at high temperature} \\ \textbf{III.}\; \text{Non-spontaneous at all temperatures} \\ \textbf{IV.}\; \text{Spontaneous at low temperature} \end{array} \\ \hline \end{array} \]
Identify from following the correct set of thermodynamic conditions for a reaction to be nonspontaneous at all temperatures.
Identify from following the correct set of thermodynamic conditions for the reaction to be spontaneous at all temperature.

Identify the correct statement from the following: 
UK 'copper' coins are Cu/Ni alloy. AgBr has special light-sensitive properties. Ti\(^{2+}\), V\(^{2+}\), Cr\(^{2+}\) are strong oxidising agents. The magnetic moment of V\(^{2+}\) is 2.84 BM.

Which of the following is present in the photochemical smog?

Match List I with List II

List IList II
APhysisorptioniSingle Layer Adsorption
BChemisorptionii20−40kJmol−1
CN2​(g)+3H2​(g)—⇢Fe(s)—⇢​2NH3​(g)iiiChromatography
DAnalytical Application or AdsorptionivHeterogeneous catalysis

Choose the correct answer from the options given below:

For independent processes at 300K
ProcessΔH/kJmol−1ΔS/JK−1
A-25-80
B-2240
C25-50
D2220

The number of non-spontaneous processes from the following is
For a reaction to be spontaneous, the required conditions are:

Given are two statements one is labelled as Assertion A and other is labelled as Reason R.

Assertion A : Magnesium can reduce Al2O3 at a temperature below 1350°C, while above 1350°C aluminium can reduce MgO.
Reason R : The melting and boiling points of magnesium are lower than those of aluminium.

In light of the above statements, choose the most appropriate answer from the options given below :

When the same quantity of heat is absorbed by a system at two different temperatures $T_1$ and $T_2$, such that $T_1 > T_2$, change in entropies are $\Delta S_1$ and $\Delta S_2$ respectively. Then
The process with negative entropy change is :

The work done in ergs for the reversible expansion of one mole of an ideal gas from a volume of 10 liters to 20 liters at 25° is

The average translational kinetic energy of a molecule in a gas becomes equal to $0.69\, eV$ at a temperature about [Boltzmann constant = $1.38 \times 10^{-23} \; J \; K^{-1}$]
In which of the following changes entropy decreases.
A certain reaction is non spontaneous at 298K. The entropy change during the reaction is 121 $JK^{-1}.$ Is the reaction is endothermic or exothermic ? The minimum value of $\Delta$H for the reaction is
Molar enthalpy change for melting of ice is $6\, kJ / mol$. Then the internal energy change (in $k J / mol$ ) when $1$ mole of water is converted into ice at $1$ atm at $0^{\circ} C$ is Empty QImg
The entropy of vaporization of a liquid is $58 \, JK^{-1} \,mol^{-1}$. If $100\, g$ of its vapour condenses at its boiling point of $123^{\circ}C$, the value of entropy change for the process is (Molar mass of the liquid = $58 \,g \,mol^{-1})$
The entropy change involved in the isothermal reversible expansion of $2$ moles of an ideal gas from a volume of $10\, dm ^{3}$ at $27^{\circ} C$ is to a volume of $100\, dm ^{3}$
Predict in which of the following entropy decreases.
In which of the following reactions, standard entropy change $(\Delta S^{\circ})$ is positive and standard Gibb?s energy change $(\Delta G^{\circ})$ decreases sharply with increasing temperature ?
Standard entropies of $X_2 ,Y_2$ and $XY_3$ are $60 , 40 $ and $ 50 \, JK^{-1} mol^{-1}$ respectively. For the reaction $ { \frac{1}{2} X_2 + \frac{3}{2}Y_2 <=> XY_3, \Delta H = -30 kJ}$ to be at equilibrium, the temperature should be
Dissolution of ammonium chloride in water leads to a cooling sensation. At constant temperature, this process is accompanied by
The change in entropy for the fusion of $1$ mole of ice is [mp of ice = $273\, K$, molar enthalpy of fusion for ice $ = 6.0\,kJ\,mol^{-1} $ ]
Condition for spontaneity in an isothermal process is
The reaction,Zn(s) + CuSO4(aq) $\rightarrow$ZnSO4(aq) + Cu(s) is an example of a