The compound, whose 0.1 M solution is basic, is:
(A) Ammonium chloride
(B) Ammonium acetate
(C) Ammonium sulphate
(D) Sodium acetate

Hint: To answer the compound which is more basic, we should know one important concept about salt. The salt will be more basic when it is composed of strong and base weak acid.

Step by step answer:
First, we should know about salt. We should know that in acid – base chemistry, salts are ionic compounds. These ionic compounds are the product from acid base neutralization reaction of an acid and a base. We know that salts are composed of cations (positively charged ions ) and anions (negative ions). We should remember that basic salt is the product of the neutralization of a strong base and a weak acid. So, by using this property we will answer our question. We will take each option and we will find which compound is more basic and why.
So, let us take the first option of ammonium chloride. We should know that ammonium chloride is an inorganic compound with the formula\[N{{H}_{4}}Cl\]. So, by looking at the chemical formula we will find that it is a salt that is composed of ammonium hydroxide base and hydrochloric acid. So, now we can say that this salt will be acidic.
Let us now take the second option. Ammonium acetate is the salt of a weak acid and a weak base. We can say that ammonium acetate creates a neutral solution when we dissolve it in water.
In the third option, we have ammonium sulphate. This is a salt of a strong acid (\[{{H}_{2}}S{{O}_{4}}\]) and weak base \[N{{H}_{3}}\]). When we dissolve this salt in water, its solution results as acidic with a pH of 5.5.
In the fourth option, sodium acetate is an organic sodium salt. It contains an acetate ion from acetic acid and sodium ion from sodium hydroxide. Sodium hydroxide is a strong base. We can say that this salt will be basic.
We discussed all the options, and now we can say that option D will be more basic. We can say that all the other options except sodium acetate are either acidic or neutral.

Note: We should note that sodium acetate can prevent bacteria cultivation in a wide range of acidic regions. It also functions as a buffer as well. When we want to add sour taste to food, we generally select acetic acid, but the combination of sodium acetate and acetic acid can make the taste mild.