Which of the following pairs of a chemical reaction is certain to result in a spontaneous reaction?
Endothermic and decreasing disorder
Exothermic and increasing disorder
Endothermic and increasing disorder
Exothermic and decreasing disorder
Identify the correct statement for change of Gibbs energy for a system (Gsystem) at constant temperature and pressure
If Gsystem = 0, the system has attained equilibrium
If Gsystem = 0, the system is still moving in a particular direction
If Gsystem = 0, the process is not spontaneous
If Gsystem = 0, the process is spontaneous
The standard emf of a galvanic cell involving cell reaction with n = 2 is found to be 0.295 V at 25°C. The equilibrium constant of the reaction would be
2.0 × 1011
4.0 × 1012
1.0 × 102
1.0 × 1010
nXm emit one α and two β- particles. It is converted into
nXm - 4
n - 1Xm - 1
nZm - 4
None of these
The strongest oxidising agent amongst F2, Cl2, Br2 and I2 is
F2
I2
Cl2
Br2
A.
F2
Since all the halogens have strong tendency to accept electrons, they act as strong oxidising agent.
F2 + 2e- → 2F- ; E° = + 2.87 V
Cl2 + 2e- → 2Cl- ; E° = +1.36 V
Br2 + 2e- → 2Br- ; E° = +1.09 V
I2 + 2e- → 2I- ; E° = +0.54 V
The electrode potential of F2 is the maximum while that of I2 the mimmum. So, F2 is the strongest oxidising agent while I2 is the weakest oxidising agent.
A compound has the empirical formula CH2O. Its vapour density is 30. Its molecular formula is
C2H4O2
C2H6O
C2H6O2
C2H4O