Strongest conjugate base is

Options

A. `(CH_3)_3CO^-`
B. `(CH_3)_2 CHO^-`
C. `CH_3CH_3O^-`
D. `CH_3O^-`

Answer

To determine the strongest conjugate base, we need to understand the relationship between acids and their conjugate bases. Here's a step-by-step solution:

### Step 1: Understand Conjugate Acid-Base Pairs
- A conjugate base is formed when an acid donates a proton (H⁺). Therefore, to identify the strongest conjugate base, we should look for the weakest acid.

### Step 2: Identify Common Acids
- Common acids include:
- Hydrochloric acid (HCl)
- Acetic acid (CH₃COOH)
- Sulfuric acid (H₂SO₄)
- Water (H₂O)

### Step 3: Determine the Strength of Acids
- The strength of an acid can be determined by its ability to donate protons. Strong acids dissociate completely in solution, while weak acids do not.
- For example:
- HCl is a strong acid.
- Acetic acid (CH₃COOH) is a weak acid.

### Step 4: Identify the Corresponding Conjugate Bases
- The conjugate bases of the acids listed above are:
- Conjugate base of HCl: Cl⁻
- Conjugate base of CH₃COOH: CH₃COO⁻
- Conjugate base of H₂SO₄: HSO₄⁻
- Conjugate base of H₂O: OH⁻

### Step 5: Compare the Strengths of Conjugate Bases
- The strength of a conjugate base is inversely related to the strength of its conjugate acid. The weaker the acid, the stronger the conjugate base.
- Among the conjugate bases identified:
- Cl⁻ is a weak base.
- CH₃COO⁻ is a stronger base than Cl⁻.
- HSO₄⁻ is a weaker base than CH₃COO⁻.
- OH⁻ is a strong base.

### Step 6: Identify the Strongest Conjugate Base
- Among the conjugate bases, OH⁻ (from water) is the strongest base because water is a very weak acid. Therefore, the strongest conjugate base is OH⁻.

### Final Answer:
- The strongest conjugate base is **OH⁻**.

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