Question

Which of the following sequences correctly represents the decreasing acidic nature of oxides?
(A) \[L{i_2}O > BeO > {B_2}{O_3} > C{O_2} > {N_2}{O_3}\]
(B) \[{N_2}{O_3} > C{O_2} > {B_2}{O_3} > BeO > L{i_2}O\]
(C) \[C{O_2} > {N_2}{O_3} > {B_2}{O_3} > BeO > L{i_2}O\]
(D) \[{B_2}{O_3} > C{O_2} > {N_2}{O_3} > L{i_2}O > BeO\]

Answer 1

Hint: as we move along the period from lithium to fluorine, the non-metallic character increases and the metallic character decreases. Metallic oxides are basic in nature and non-metallic nature are acidic in nature. Thus, from lithium to fluorine, acidic nature of oxides increases.

Complete Step by Step Solution:
Metallic oxides are basic in nature. This can be proved from the fact that metallic oxides react with acids to form salt and water. This can be compared to the neutralisation reaction acid with base to give salt and water. Examples of metallic oxide are lithium oxide, magnesium oxide.

So as the metallic character decreases, basic character decreases and acidic character increases. This is because on moving from left to right in a period, nature to accept electrons increases for octet completion. Out of \[L{i_2}O,BeO,{B_2}{O_3},C{O_2},{N_2}{O_3}\], it is ${N_2}{0_3}$which is most non-metallic and thus, most acidic.
Also, the acidic nature is directly proportional to the positive oxidation state of the central metal atom. Thus, the overall order is\[{N_2}{O_3} > C{O_2} > {B_2}{O_3} > BeO > L{i_2}O\].
Thus, the correct answer is II.

Note: Some oxides are both acidic and basic, they are known as amphoteric oxides. For example, . Nature of oxides can be studied using the electronegativity concept of oxygen and hydrogen atoms. The difference in electronegativity of oxygen and hydrogen is $1.4$. Consider a compound. If the electronegativity difference of A and oxygen is greater than $1.4$ then it is a basic oxide. If the difference is less than $1.4$then it called acidic oxide. If the difference is equal to $1.4$ then it is termed as amphoteric oxide. There is another type of oxides that are neither acidic nor basic, but they are neutral oxides. Example: $CO$.