1. Why does not fluorene dissolve in 1.5M sodium hydroxide solution?
2. What experimental difficulty would you encounter if you had neclected to include a drying step before evaporating the ether solution of the neutral organic compound (fluorene)?
1. Well, it seems like fluorene is playing hard to get with sodium hydroxide. Maybe it's just not interested in a strong basic solution. It's like going to a party and avoiding all the small talk. Fluorene just wants to be left alone, I guess.
2. Ah, the classic case of forgetting to dry your organic compound. It's like going out in the rain without an umbrella - things are going to get messy. When you evaporate the ether solution without drying it first, you'll be left with a not-so-neat residue. It's like trying to clean spilled milk with a regular napkin. So remember, always dry before you evaporate, unless you're going for the "Oops, I made a mess" look.
1. Fluorene does not dissolve in 1.5M sodium hydroxide solution because it is insoluble in water-based solutions. Sodium hydroxide is a strong base and has a high solubility in water, but fluorene is a nonpolar compound and is practically insoluble in water. Since sodium hydroxide is water-based, it cannot effectively dissolve fluorene. Nonpolar compounds are generally soluble in nonpolar solvents, such as ethers or hydrocarbons, but not in polar solvents like water.
To determine solubility of a compound in a particular solvent, one can consider the nature of the compound's intermolecular forces. Fluorene has predominantly London dispersion forces which arise from temporary shifts in electron density in the molecules. These forces are weak compared to the dipole-dipole or hydrogen bonding forces present in polar solutions, like sodium hydroxide dissolved in water. These weak forces cause fluorene to have limited solubility in polar solvents.
2. If you neglect to include a drying step before evaporating the ether solution of the organic compound fluorene, you may encounter some experimental difficulties. Drying is an important step in organic synthesis to remove any residual solvent, in this case, ether. Neglecting to dry the solution properly can lead to the following difficulties:
- Contaminated product: If the ether solution is not dried adequately, residual water or other impurities may remain in the solution. These impurities can contaminate the product and affect its purity and yield.
- Longer evaporation time: Ether is a volatile organic solvent with a low boiling point. If the solution contains moisture, the presence of water will increase the boiling point and hinder the evaporation process. This can prolong the time required to evaporate the solvent and recover the solid compound.
- Loss of product: Inadequate drying of the ether solution can result in the loss of the compound being synthesized. If the solution is not completely dried before evaporation, some of the compound may be lost along with the remaining solvent.
To avoid these difficulties, it is crucial to include a proper drying step before evaporating the ether solution. This can be done by using desiccants or drying agents such as anhydrous sodium sulfate or magnesium sulfate to remove any traces of water or impurities present in the solution.