Air is made up of different gases, such as oxygen, nitrogen, and carbon dioxide. which statement best describes these three components of air? they are all classified as pure substances. they cannot react with another substance. they are chemically bonded to one another. they can be classified as elements.

Answer : Option A) They are all classified as pure substances.

Explanation : Air is a mixture of gases which is mainly made up of different gases, such as oxygen, nitrogen, and carbon dioxide. Oxygen exists in the pure forms and exists in nature in free state and also in combined state. Oxygen is also found in air in a triatomic form, which is called ozone.

Nitrogen gas exists in nature in abundance as compared to others, nitrogen is found in free state. Carbon dioxide is a pure substances which readily exists in nature in combined form as carbon is less stable.

answer: - 3.) the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.

solution: - as per the rules, oxidation number of oxygen in its compounds is -2. the sum of oxidation numbers of all the elements of a molecule or compound is zero.

also, the oxidation number in elemental form is zero.

in no, the oxidation number of o is -2 so the oxidation number of n is +2 so that the sum is zero.

similarly, the oxidation number of c in co is +2 and o is -2.

on product side the oxidation number of n is 0 as it is in the elemental form() .

oxidation number of c in carbon dioxide is +4 as there are two oxygen in it and we know that each oxygen is -2.

so, oxidation number of n is changing from +2 to 0 and the oxidation number of c is changing from +2 to +4.

since nitrogen is reduced and hence no is acting as an oxidizing agent. carbon is oxidized and so co is acting as a reducing agent.

so, the right choice is number 3.)the oxidation state of nitrogen in no changes from +2 to 0, and the oxidation state of carbon in co changes from +2 to +4 as the reaction proceeds.