To determine which of the given options is a base, let's analyze each compound one by one:
1. [tex]$Ca(OH)_2$[/tex] (Calcium Hydroxide):
- Calcium hydroxide is commonly known as slaked lime or hydrated lime.
- It is a strong base because it dissociates fully in water to give calcium ions ([tex]$Ca^{2+}$[/tex]) and hydroxide ions ([tex]$OH^-$[/tex]).
2. AgO (Silver Oxide):
- Silver oxide is a metal oxide.
- It generally reacts with acids to form salts and water, but it is not characterized as a base in the common sense.
3. NaCl (Sodium Chloride):
- Sodium chloride is commonly known as table salt.
- It is a neutral salt resulting from the reaction of hydrochloric acid (HCl) and sodium hydroxide (NaOH), and it does not exhibit basic properties.
4. HF (Hydrofluoric Acid):
- Hydrofluoric acid is a weak acid.
- It does not exhibit the basic properties; instead, it dissociates to release hydrogen ions ([tex]$H^+$[/tex]) in solution.
After analyzing each compound, we conclude that:
- [tex]$Ca(OH)_2$[/tex] (Calcium Hydroxide) is the base among the given options.
Therefore, the correct answer, which is a base, is:
[tex]$Ca(OH)_2$[/tex].
