Question

____ is a technique to physically separate a heterogeneous mixture of a solid and a liquid.
○ spectrophotometry
○ base hydrolysis
○ filtration
○ saponification

Explanation:

We need to identify the technique for physically separating a heterogeneous solid - liquid mixture.

• Spectrophotometry is used for measuring the concentration of a substance in a solution by its light absorption, not for separation.
• Base hydrolysis is a chemical reaction (hydrolysis in basic conditions), not a physical separation technique.
• Saponification is the reaction of fats with bases to form soap, a chemical process.
• Filtration is a physical technique that uses a filter medium to separate solid particles from a liquid in a heterogeneous mixture.

Answer:

Filtration (the option with text "Filtration")