To determine the conjugate base of [tex]\( H_2O \)[/tex], we need to understand some basic acid-base chemistry, particularly the concept of conjugate acid-base pairs.
1. Understanding Acids and Bases:
- An acid is a substance that can donate a proton (H+).
- A base is a substance that can accept a proton (H+).
2. What is a Conjugate Base?:
- The conjugate base of an acid is what remains after the acid has donated a proton.
- In simpler terms, we remove an H+ from the acid to get its conjugate base.
3. Applying to [tex]\( H_2O \)[/tex]:
- [tex]\( H_2O \)[/tex] can act as an acid by donating a proton (H+).
- When [tex]\( H_2O \)[/tex] loses a proton (H+), it turns into [tex]\( OH^- \)[/tex].
Therefore, the conjugate base of [tex]\( H_2O \)[/tex] is [tex]\( OH^- \)[/tex].
Thus, among the given options:
- [tex]\( O^{2-} \)[/tex] – This is incorrect.
- [tex]\( H_3O^+ \)[/tex] – This is incorrect, as it's actually the hydronium ion, which is the conjugate acid of water.
- [tex]\( OH^- \)[/tex] – This is correct.
- [tex]\( H_2O \)[/tex] – This is incorrect, as it cannot be its own conjugate base.
- [tex]\( H_2O \)[/tex] has no conjugate base – This is incorrect because every acid has a conjugate base.
The correct answer is [tex]\( OH^{-} \)[/tex].
