Understanding pKa

* pKa is the negative logarithm (base 10) of the acid dissociation constant (Ka).

* It's a measure of the acid's strength:

* Lower pKa values indicate stronger acids.

* Higher pKa values indicate weaker acids.

Calculation

1. The Formula: pKa = -log(Ka)

2. Plug in the Ka value: pKa = -log(5.4 x 10⁻¹⁰)

3. Calculate: pKa ≈ 9.27

Therefore, the pKa of the unknown weak acid is approximately 9.27.