WHY IS ORTHO NITROPHENOL STEAM VOLATILE?

There are several reasons why ortho nitrophenol is steam volatile.

1. Low Molecular Weight:

• Ortho nitrophenol possesses a relatively low molecular weight of 139.11 g/mol.
• Steam volatility tends to enhance as molecular weight decreases, allowing ortho nitrophenol to vaporize readily with steam.

2. Polarity and Hydrogen Bonding:

• Ortho nitrophenol contains a polar nitro group (-NO2) and a hydroxyl group (-OH) but lacks extensive hydrogen bonding capabilities.
• The presence of these polar groups contributes to its water solubility, yet the limited hydrogen bonding allows it to escape into the vapor phase during steaming.

3. Intramolecular Hydrogen Bonding:

• Ortho nitrophenol exhibits intramolecular hydrogen bonding between the hydroxyl (-OH) and nitro (-NO2) groups.
• This internal interaction reduces the availability of the hydroxyl group for intermolecular hydrogen bonding with water molecules.
• Consequently, ortho nitrophenol tends to partition into the vapor phase rather than forming extensive hydrogen bonds with water.

4. Enhanced Vapor Pressure:

• The intramolecular hydrogen bonding in ortho nitrophenol elevates its vapor pressure.
• A higher vapor pressure facilitates the compound's vaporization and transport into the steam phase.

5. Steam Distillation:

• Steam distillation is a technique commonly employed for the purification or extraction of volatile compounds from mixtures.
• During steam distillation, the steam carries the volatile compound (ortho nitrophenol in this case) along with it, facilitating its separation from the bulk mixture.

Conclusion:

Ortho nitrophenol's volatility in steam can be attributed to its low molecular weight, limited hydrogen bonding capabilities, intramolecular hydrogen bonding, elevated vapor pressure, and the process of steam distillation. These factors collectively contribute to its effective separation and purification through steam-based techniques.

Frequently Asked Questions:

1. What is the significance of ortho nitrophenol's steam volatility?

   • Ortho nitrophenol's steam volatility enables its efficient separation and purification through steam distillation, making it valuable in various industrial and laboratory processes.

2. Does temperature influence ortho nitrophenol's steam volatility?

   • Yes, temperature plays a crucial role. As temperature increases, the vapor pressure of ortho nitrophenol rises, enhancing its steam volatility and facilitating its transfer into the vapor phase.

3. Are there any limitations to ortho nitrophenol's steam volatility?

   • While ortho nitrophenol exhibits steam volatility, the presence of other non-volatile compounds in the mixture may hinder its complete vaporization. Additionally, factors such as pressure and the efficiency of the steam distillation apparatus can influence the extent of its volatility.

4. What safety precautions should be taken when working with ortho nitrophenol?

   • Ortho nitrophenol is a toxic and corrosive compound. Proper protective measures, including gloves, eye protection, and appropriate ventilation, are essential to minimize exposure and potential hazards.

5. What are some industrial applications of ortho nitrophenol's steam volatility?

   • Ortho nitrophenol's steam volatility finds applications in various industries, including pharmaceuticals, dyes, and pesticides. It is also utilized in the production of explosives and as an intermediate in the synthesis of other organic compounds.