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
18 carat gold contains
18% gold
24% gold
75% gold
60% gold
C.
75% gold
The weight of gold in jewellery is expressed in carats. It simply implies the number of parts by weight of gold in 24 parts by weight of the alloy.
Pure gold is 24 carats. 18 carat gold means that it contains 18 parts by weight ofpure gold in 24 parts by weight of the alloy.
% of gold =
% of gold = 75%
A compound has the empirical formula CH2O. Its vapour density is 30. Its molecular formula is
C2H4O2
C2H6O
C2H6O2
C2H4O