Carbon can reduce ferric oxide to iron at a temperature above 983 K because
carbon monoxide formed is thermodynamically less stable than ferric oxide
carbon has a higher affinity towards oxidation than iron
free energy change for the formation of carbon dioxide is less negative than that for ferric oxide
iron has a higher affinity towards oxygen than carbon
B.
carbon has a higher affinity towards oxidation than iron
Above 983 K, free energy change for the formation of CO2, is more negative than that for ferric oxide. Thus, above this temperature, carbon has a higher affinity towards oxidation than iron.
Generally, the first ionisation energy increases along a period. But there are some exceptions. The one which is not an exception is
Be and B
Na and Mg
Mg and Al
N and O
A metallic oxide reacts with water to from its hydroxide, hydrogen peroxide and also liberates oxygen. The metallic oxide could be
CaO
KO2
Li2O
Na2O2
The correct order of ionisation energy of C, N, O, F is
F < O < N < C
F < N < C < O
C < N < O < F
C < O < N < F
The oxide of an element whose electronic configuration is 1s2, 2s2, 2p6, 3s1 is
neutral
amphoteric
basic
acidic
The correct order of ionisation energy of C, N, O and F is
C < N < O < F
C < O < N < F
F < O < N < C
F < N < C < O
The order of stability of metal oxides is
Al2O3 < MgO < Fe2O3 < Cr2O3
Cr2O3 < MgO < Al2O3 < Fe2O3
Fe2O3 < Cr2O3 < Al2O3 < MgO
Fe2O3 < Al2O3 < Cr2O3 < MgO
An ionic compound is expected to have tetrahedral structure if r+/r- lies in the range of
0.414 to 0.732
0.225 to 0.414
0.155 to 0.225
0.732 to 1
The correct order of electronegativities of N, O, F and P is
F > O > P > N
F > O > N > P
N > O > F > P
F > N > P > O
