Which of the following solvent can be used for water content determination with Dean-Stark apparatus present in our lab?

An azeotropic mixture of toluene and water distills out of the reaction, but only the toluene (density 0.865 g/ml) returns, since it floats on top of the water (density 0.998 g/ml), which collects in the trap.

What must be true to ensure that the water layer collects at the bottom of the trap?

What must be TRUE to ensure that the water layer collects at the bottom of the trap? The organic solvent must be less dense than water.

What is reflux condenser?

A reflux condenser is an apparatus commonly used in organic chemistry to prevent reactant or solvent loss in a heated chemical reaction. For chemical reactions that need to be carried out at elevated temperatures over long periods of time a reflux system can be used to prevent the loss of solvent through evaporation.

What are Dean Stark conditions?

A Dean-Stark trap is a special piece of glassware, which allows the collection of water during a reaction through an azeotropic distillation. The desire to collect water from a reaction can have various reasons. It can drive the equilibria in reactions, where water is formed as a byproduct.

How is water removed during a reaction?

In many synthetic reactions water is formed, which is normally removed by drying agents such as Na2S04 and molecular sieves or alternatively by azeotropic distillation employing auxiliary solvents such as toluene or xylene.

What is the purpose of the Dean Stark trap?

What is a Dean Stark trap typically used for?

A Dean-Stark trap is a specialized piece of glassware used for continuously removing water formed in a chemical reaction.

Why is heating under reflux used?

However, many organic compounds have low boiling points and will vaporise upon exposure to such high heat, preventing the reaction from proceeding in full. To address this, heating under reflux is used. This refers to heating a solution with an attached condenser to prevent reagents from escaping.

What is the purpose of heating under reflux?

heating under reflux is used to address this To prevent reagents from escaping, a solution with an attached condenser is needed. Vapor will flow back into the flask from the cool surface of the attached Condenser.

Why do we need reflux in distillation?

The purpose of reflux is to provide down-flowing liquid throughout the rectification section to contact with the up-flowing vapor in order to achieve stage-by-stage equilibrium heat and mass transfer and, hence, purification of the top product.

What is the purpose of a Dean Stark trap?

Dean-Stark traps are commonly used to remove water from a solvent mixture under various circumstances. For example, the removal of water through a simple distillation when water does not form an azeotrope with the other solvent, is possible with a Dean-Stark trap based on its design.

What does the Dean and Stark distillation measure look like?

The Dean-Stark trap was invented by two American chemists, Ernest Dean and David Stark, to allow the determination of the amount of water in petroleum, and it is now used to remove water from reactions in which water is a product, helping to drive the reaction to completion. Here is what it looks like:

Which is a modification of the Dean Stark trap?

Modified Dean-Stark trap allows for more efficient cooling and separation of the azeotrope during distillation. Graduated from 0 to 10ml in 0.2mL subdivisions. **Design suggested by Dr. Craig Merlic, University of California, Los Angeles, California

Where does the solvent go in a Dean Stark apparatus?

More rarely encountered is the model for solvents with a density greater than water. This type has a tube at the bottom of the side-arm to allow the organic solvent at the bottom to flow back into the reaction vessel.

Who was the inventor of the Dean Stark reactor?

Dean–Stark apparatus. It is used in combination with a reflux condenser and a batch reactor for continuous removal of the water that is produced during a chemical reaction performed at reflux temperature. It was invented by the American chemists Ernest Woodward Dean (1888–1959) and David Dewey Stark…