Concept:The base dissociation constant (\( K_b \)) is a measure of base strength. Strong bases completely dissociate in water and have exceptionally high \( K_b \) values.
Formula:$$ K_b = \frac{[B^+][\text{OH}^-]}{[B\text{OH}]} $$
Solution:- \( \text{NaOH} \) is an alkali metal hydroxide, which makes it a very strong base that dissociates \( \approx 100\% \) in aqueous solutions.
- Because the denominator \( [B\text{OH}] \) approaches zero, its \( K_b \) value is astronomically large compared to weak bases.
- \( \text{NH}_4\text{OH} \) and \( \text{CH}_3\text{NH}_2 \) are weak bases. \( \text{Ca(OH)}_2 \) is a strong base but has lower solubility than NaOH.
Why other options are incorrect:Weak bases have \( K_b \) values typically in the range of \( 10^{-4} \) to \( 10^{-10} \), which are infinitely smaller than a strong base like \( \text{NaOH} \).
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