Define a salt. Give three examples of salts with their chemical formulae.

Here are the answers to your chemistry assignment, Balogun:

1. Define a salt. Give three examples of salts with their chemical formulae. A salt is an ionic compound formed when the hydrogen ion of an acid is replaced by a metal ion or an ammonium ion. It is typically formed from the reaction of an acid with a base. Three examples of salts with their chemical formulae are:

   • Sodium chloride: $\boxed{\text{NaCl}}$
   • Potassium nitrate: $\boxed{\text{KNO}_3}$
   • Calcium sulfate: $\boxed{\text{CaSO}_4}$

2. List five uses of salts. Five uses of salts are:

   • Food preservation (e.g., sodium chloride for curing meat and fish).
   • Seasoning food (e.g., table salt, NaCl).
   • Fertilizers in agriculture (e.g., ammonium nitrate, potassium chloride).
   • Manufacturing of chemicals (e.g., sodium chloride for producing chlorine, sodium hydroxide).
   • Medicinal purposes (e.g., Epsom salts, $\text{MgSO}_4 \cdot 7\text{H}_2\text{O}$, as a laxative).

3. What is solubility? Solubility is the maximum amount of a solute that can dissolve in a given amount of solvent at a specific temperature to form a saturated solution. It is often expressed in grams of solute per 100 grams of solvent.

4. Explain any two methods of preparing salts. For each method, give one example of a salt that can be prepared and write the corresponding chemical equation.

   • Method 1: Neutralization (Reaction of an acid with a base) This method involves reacting an acid with a soluble base (alkali) to form a salt and water. The acid's hydrogen ions react with the base's hydroxide ions. This method is suitable for preparing soluble salts.

     • Example: Preparation of sodium chloride ($\text{NaCl}$)
     $$\text{HCl(aq)} + \text{NaOH(aq)} \longrightarrow \text{NaCl(aq)} + \text{H}_2\text{O(l)}$$

   • Method 2: Reaction of an acid with a metal This method involves reacting a dilute acid with a reactive metal (above hydrogen in the reactivity series) to produce a salt and hydrogen gas. This method is suitable for preparing soluble salts of reactive metals.

     • Example: Preparation of zinc sulfate ($\text{ZnSO}_4$)
     $$\text{Zn(s)} + \text{H}_2\text{SO}_4\text{(aq)} \longrightarrow \text{ZnSO}_4\text{(aq)} + \text{H}_2\text{(g)}$$