Chemistry 2007 JAMB Past Questions - Question 22: Dissolving some pellets of NaOH in water would result in

Correct Answer

D

Explanation

Dissolving some pellets of NaOH in water would result in the following:

**1. Formation of a sodium hydroxide solution:** The NaOH pellets will dissociate into individual sodium (Na⁺) and hydroxide (OH⁻) ions when added to water. This creates a **sodium hydroxide solution (NaOH(aq))**.

**2. Exothermic reaction:** The dissolving process is **exothermic**, meaning it releases heat. You might notice the container feeling warm as the pellets dissolve.

**3. Increase in pH:** Sodium hydroxide is a strong base, meaning it readily donates hydroxide ions to the solution. This increases the concentration of hydroxide ions, making the solution **basic** and raising the **pH** above 7.

**4. Potential safety hazards:** NaOH is a caustic substance that can irritate skin and eyes, and even cause burns. It's important to handle it with proper care and wear appropriate personal protective equipment (PPE) like gloves and goggles.
  
* The concentration of the NaOH solution depends on the amount of NaOH pellets dissolved and the volume of water used.
* The temperature change during the dissolving process depends on the amount of NaOH used and the initial temperature of the water.
* The specific pH of the solution will depend on the concentration of the NaOH solution.

Remember, it's crucial to handle NaOH with caution and follow proper safety procedures.