How many of the following groups are ortho,para directing and ring activating?
`-NO_(2), -CN, -CH_(3), -OH, -NH_(2),`
`-OR, -X, -CHO, -NHR`

Answer

To determine how many of the given groups are ortho, para directing and ring activating, we will analyze each group one by one based on their electronic effects on the aromatic ring.

### Step-by-Step Solution:

1. **Identify the Groups**: We have the following groups to analyze:
- -NO₂ (Nitro group)
- -CN (Cyanide group)
- -CH₃ (Methyl group)
- -OH (Hydroxyl group)
- -NH₂ (Amino group)
- -OR (Alkoxy group)
- -X (Halogen)
- -CHO (Aldehyde group)
- -NHR (Amino group with R)

2. **Analyze Each Group**:
- **-NO₂**: This is a strong electron-withdrawing group due to its -I (inductive) and -M (mesomeric) effects. It decreases electron density on the ring, making it meta-directing and ring deactivating.
- **-CN**: Similar to -NO₂, the cyanide group is also electron-withdrawing and meta-directing. It pulls electron density away from the ring.
- **-CH₃**: The methyl group is an electron-donating group via hyperconjugation (+H effect). It increases electron density at the ortho and para positions, making it ortho-para directing and ring activating.
- **-OH**: The hydroxyl group donates electron density to the ring through resonance (+R effect), increasing electron density at ortho and para positions. Thus, it is ortho-para directing and ring activating.
- **-NH₂**: The amino group also donates electron density through resonance (+R effect), making it ortho-para directing and ring activating.
- **-OR**: Alkoxy groups are similar to -OH in that they donate electron density to the ring. Therefore, they are ortho-para directing and ring activating.
- **-X (Halogens)**: Halogens have a -I effect (electron-withdrawing) but also a +R effect (electron-donating). However, the -I effect is stronger, making them ortho-para directing but ring deactivating.
- **-CHO**: The aldehyde group is an electron-withdrawing group (-I effect), making it meta-directing and ring deactivating.
- **-NHR**: Similar to -NH₂, the NHR group donates electron density through resonance (+R effect), making it ortho-para directing and ring activating.

3. **Count the Groups**:
- The groups that are ortho-para directing and ring activating are:
- -CH₃
- -OH
- -NH₂
- -OR
- -NHR
- Total: 5 groups.

### Final Answer:
Out of the given groups, **5 groups** are ortho, para directing and ring activating.