Organic Chemistry Reactions and Techniques

Flashcards from organic chemistry lecture notes.

What type of reaction is reflux used for in the context of primary alcohols?

Oxidation of a primary alcohol to a carboxylic acid using potassium dichromate(VI) and dilute sulfuric acid.

What are the necessary conditions of reflux for the oxidation of primary alcohols to carboxylic acids?

Excess dichromate and heat under reflux.

What is the observation during the oxidation of a primary alcohol to a carboxylic acid using dichromate?

Orange dichromate solution changes to a green color of Cr3+ ions.

Why is reflux used when heating organic reaction mixtures?

To prevent organic vapors from escaping by condensing them back to liquids, allowing for heating for longer periods.

Why should the end of the condenser never be sealed during reflux?

The buildup of gas pressure could cause the apparatus to explode.

What is the purpose of anti-bumping granules?

To prevent vigorous, uneven boiling by making small bubbles form instead of large bubbles.

Why are electric heaters often used to heat organic chemicals?

Organic chemicals are normally highly flammable and could set on fire with a naked flame.

What is distillation generally used for?

As a separation technique to separate an organic product from its reacting mixture.

What type of reaction occurs when using distillation for a primary alcohol?

Oxidation of a primary alcohol to an aldehyde using potassium dichromate(VI) solution and dilute sulfuric acid.

What are the necessary conditions of distillation in the context of primary alcohols?

Use a limited amount of dichromate, warm gently, and distil out the aldehyde as it forms.

What should the drying agent NOT do when purifying an organic liquid?

React with the organic liquid.

What two solutions can be used to wash the product in a separating funnel during purification?

Sodium hydrogencarbonate solution and saturated sodium chloride solution.

What is the purpose of using sodium hydrogencarbonate solution during purification?

To neutralize any remaining reactant acid.

What is the purpose of using saturated sodium chloride solution during purification?

To help separate the organic layer from the aqueous layer.

What does 'decant' mean in the context of organic liquid purification?

Carefully pour off organic liquid leaving the drying agent in the conical flask.

What type of reaction is Br2 or Cl2 with UV light?

Free radical substitution.

What type of reaction is HBr or HCl at room temperature?

Electrophilic addition.

What is the product if a primary alcohol is heated gently and distilled with Na2Cr2O7/H+?

Aldehyde. (Partial oxidation)

What is the product if a secondary alcohol is heated under reflux with Na2Cr2O7/H+?

Ketone (Oxidation)

What type of reaction is KOH aqueous, heat under reflux?

Nucleophilic substitution.

What type of reaction are Conc H2SO4 + sodium halide, heat under reflux?

Substitution.