What sorts of informations can you draw from the following reaction ?
(CN)2(g) + 2OH-(aq) → CN-(aq) + CNO-(aq) + H2O(l)
The oxidation numbers of carbon in (CN)2, CN- and CNO- are +3, +2 and +4 respectively.
These are obtained as shown below:
Let the oxidation number of C be x.
(CN)2
2(x - 3) = 0
∴x = 3
CN-
x - 3 = -1
∴x = 2
CNO-
x -3 - 2 =-1
∴x = 4
The oxidation number of carbon in the various species is:
(C+3N)2(g) + 2OH-(aq) → C+2N-(aq) + C+4NO-(aq) + H2O(l)
It can be easily observed that the same compound is being reduced and oxidised simultaneously in the given equation. Reactions in which the same compound is reduced and oxidised is known as disproportionation reactions. Thus, it can be said that the alkaline decomposition of cyanogen is an example of disproportionation reaction.
The first (ΔiH1) and the second (ΔiH) ionization enthalpies (in kJ mol–1) and the (ΔegH) electron gain enthalpy (in kJ mol–1) of a few elements are given below:
Elements | ΔiH1 | ΔiH | ΔegH |
I | 520 | 7300 | -60 |
II | 419 | 3051 | -48 |
III | 1681 | 3374 | -328 |
IV | 1008 | 1846 | -295 |
V | 2372 | 5251 | +48 |
VI | 738 | 1451 | -40 |
Which of the above elements is likely to be :
(a) the least reactive element.
(b) the most reactive metal.
(c) the most reactive non-metal.
(d) the least reactive non-metal.
(e) the metal which can form a stable binary halide of the formula MX2, (X=halogen).
(f) the metal which can form a predominantly stable covalent halide of the formula MX (X=halogen)?
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Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 20: What sorts of informations can you draw from the following reaction ? (CN)2(g) + 2OH-....
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