The incorrect statement for alcohol is:

Options

A. The-OH group is alcohols is involved in hydrogen bonding
B. Lower members have a pleasant smell and higher members are colourless and tasteless
C. Lower members are insoluble in water and organic solvents but the solubility regularly increases with molecular mass
D. Their boiling points rise fairly uniformly with rising molecular weight

Explanation

To determine the incorrect statement regarding alcohols, we will analyze each statement one by one:

1. **Statement 1**: "The OH group in alcohol is involved in hydrogen bonding."
- **Analysis**: The hydroxyl (OH) group in alcohols can indeed form hydrogen bonds due to the electronegativity of oxygen and the presence of lone pairs. This is a correct statement.

2. **Statement 2**: "Lower members have a pleasant smell and higher members are colorless and tasteless."
- **Analysis**: Lower molecular weight alcohols, such as methanol and ethanol, do have a pleasant smell. Higher molecular weight alcohols tend to be colorless and tasteless. This statement is also correct.

3. **Statement 3**: "Lower members are insoluble in water and organic solvents but the solubility regularly increases with molecular mass."
- **Analysis**: Lower members of alcohols (like methanol and ethanol) are actually soluble in water due to their ability to form hydrogen bonds with water molecules. As the molecular weight increases, the solubility in water decreases because the non-polar hydrocarbon part becomes more dominant. Therefore, this statement is incorrect.

4. **Statement 4**: "Their boiling points rise fairly uniformly with rising molecular weight."
- **Analysis**: Generally, the boiling points of alcohols do increase with molecular weight due to increased van der Waals forces. This statement is correct.

**Conclusion**: The incorrect statement is Statement 3: "Lower members are insoluble in water and organic solvents but the solubility regularly increases with molecular mass."