When sodium hydroxide dissolves in water, it dissociates to form ions, which makes sodium hydroxide a(n) base.

When sodium hydroxide (NaOH) dissolves in water, it undergoes a process called dissociation. Here's the step-by-step process:

1. Sodium hydroxide is added to water.
2. The sodium hydroxide (NaOH) dissociates, or breaks apart, into its individual ions in the water. This is represented by the chemical equation: NaOH -> Na+ + OH-
3. The sodium ions (Na+) are positively charged and the hydroxide ions (OH-) are negatively charged.
4. The presence of hydroxide ions (OH-) makes the solution basic. This is because bases are defined as substances that can accept protons (H+) or, equivalently, donate pairs of electrons and/or hydroxide ions.
5. Therefore, sodium hydroxide is considered a strong base because it completely dissociates in water to yield a large amount of hydroxide ions, increasing the pH of the solution.