Calculate The Ph Value of 0.01 M Naoh

What is pH?

The pH scale measures how acidic or basic a solution is. It ranges from 0 to 14, where:

• pH 0-6 is acidic
• pH 7 is neutral
• pH 8-14 is basic

The pH is calculated using the hydrogen ion concentration [H⁺] in moles per liter (M):

For strong bases like NaOH, the [H⁺] is determined by the concentration of the hydroxide ions [OH⁻] and the dissociation constant of water (Kw = 1.0 × 10⁻¹⁴ at 25°C).

Calculating pH

To calculate the pH of a strong base solution like NaOH, follow these steps:

1. Determine the concentration of hydroxide ions [OH⁻] from the given concentration of NaOH
2. Calculate the hydrogen ion concentration [H⁺] using Kw = [H⁺][OH⁻]
3. Calculate the pH using the formula above

pH of NaOH Solutions

Sodium hydroxide (NaOH) is a strong base that completely dissociates in water. The concentration of hydroxide ions [OH⁻] is equal to the concentration of NaOH.

For a 0.01 M NaOH solution:

• [OH⁻] = 0.01 M
• [H⁺] = Kw / [OH⁻] = 1.0 × 10⁻¹⁴ / 0.01 = 1.0 × 10⁻¹² M
• pH = -log(1.0 × 10⁻¹²) = 12.0

This calculation shows that a 0.01 M NaOH solution has a pH of 12.0, which is strongly basic.

Example Calculation

Let's calculate the pH of a 0.01 M NaOH solution step by step:

1. Given: [NaOH] = 0.01 M
2. Since NaOH is a strong base, [OH⁻] = [NaOH] = 0.01 M
3. Using Kw = [H⁺][OH⁻]:
4. [H⁺] = Kw / [OH⁻] = 1.0 × 10⁻¹⁴ / 0.01 = 1.0 × 10⁻¹² M
5. pH = -log[H⁺] = -log(1.0 × 10⁻¹²) = 12.0

The calculation confirms that the pH of a 0.01 M NaOH solution is 12.0.