Examples of electron withdrawing groups relative to hydrogen are

Options

A. `-NO_2`
B. -COOH
C. -COOR
D. All of the above

Answer

To answer the question regarding examples of electron withdrawing groups (EWGs) relative to hydrogen, we can follow these steps:

### Step 1: Understand the Concept of Electron Withdrawing Groups
Electron withdrawing groups are substituents that pull electron density away from the rest of the molecule. They are typically more electronegative than hydrogen, which has an electronegativity of 2.1 on the Pauling scale.

### Step 2: Identify Electronegativity Values
To determine if a group is an electron withdrawing group, we need to compare its electronegativity to that of hydrogen. Here are some common groups and their electronegativities:
- Nitrogen (N) has an electronegativity of approximately 3.0.
- Oxygen (O) has an electronegativity of approximately 3.5.
- Fluorine (F) has an electronegativity of approximately 4.0.
- The nitro group (NO2) is also considered an electron withdrawing group.

### Step 3: List Examples of Electron Withdrawing Groups
Based on the electronegativity values, we can identify the following as electron withdrawing groups relative to hydrogen:
1. **Nitro group (–NO2)**
2. **Cyano group (–CN)**
3. **Halogens (–F, –Cl, –Br, –I)**
4. **Carbonyl group (–C=O)**
5. **Amino group (–NH2)**
6. **Sulfonyl group (–SO2R)**

### Step 4: Conclusion
Thus, the examples of electron withdrawing groups relative to hydrogen include the nitro group (–NO2), cyano group (–CN), halogens (–F, –Cl, –Br, –I), carbonyl group (–C=O), amino group (–NH2), and sulfonyl group (–SO2R).

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