Which apparatus is used to separate two immiscible liquids and is used in purification process by liquid-liquid extraction?

Which apparatus is used to separate two immiscible liquids and is used in purification process by liquid-liquid extraction?

• A. Three Neck Flasks
• B. Separatory Funnels
• C. Graduated Cylinder
• D. Erlenmeyer Flask

Answer: (D)

Separating two immiscible liquids in a purification step that uses liquid-liquid extraction relies on a device that can hold two distinct liquid layers and let one be removed cleanly. A separatory funnel is built for this purpose: it is a pear-shaped glass container with a stopper at the top and a stopcock at the bottom. After mixing the two liquids and letting them settle, you see two separate layers because they don’t mix. Opening the stopcock lets you drain the bottom layer into another vessel while keeping the top layer in the funnel. This makes it easy to transfer one phase and then repeat the extraction with fresh solvent to maximize transfer of the solute. Other glassware aren’t as well suited for this task. A three-neck flask is designed for reactions requiring several connections, not for clean phase separation. A graduated cylinder is for measuring volumes, not for separating liquids. An Erlenmeyer flask can mix and heat solutions but lacks a stopcock and the shape needed for reliable phase separation.

Separating two immiscible liquids in a purification step that uses liquid-liquid extraction relies on a device that can hold two distinct liquid layers and let one be removed cleanly. A separatory funnel is built for this purpose: it is a pear-shaped glass container with a stopper at the top and a stopcock at the bottom. After mixing the two liquids and letting them settle, you see two separate layers because they don’t mix. Opening the stopcock lets you drain the bottom layer into another vessel while keeping the top layer in the funnel. This makes it easy to transfer one phase and then repeat the extraction with fresh solvent to maximize transfer of the solute.

Other glassware aren’t as well suited for this task. A three-neck flask is designed for reactions requiring several connections, not for clean phase separation. A graduated cylinder is for measuring volumes, not for separating liquids. An Erlenmeyer flask can mix and heat solutions but lacks a stopcock and the shape needed for reliable phase separation.