Which of the following statements are true of buffer solutions? 1. a buffer solution can be made by mixing equal concentrations of acetic acid and sodium acetate. 2. a buffer solution can be made by mixing equal concentrations of hydrochloric acid and sodium chloride. 3. a buffer solution resists changes in ph when small quantities of acid or base are added.

Option 1 and 3 are correct.

Explanation:

Buffer solution is the solution which resists the change in the magnitude of the pH when small additions of either acid or base is added.  Buffer solutions consist of weak acid and its conjugate base usually which are mixed in relatively equal and large quantities.

Hence,

Option 1. is correct because acetic acid is a weak acid and sodium acetate is the conjugate base of it which are mixed in equal concentrations.

Option 2. is incorrect because HCl and NaCl are both strong acid and salt respectively and will not form a buffer.

Option 3. is correct which is the definition of a buffer solution.

Option 1 and 3 are correct.

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.