What is the purpose of the displacement method when measuring plastic fats?

• A. To pack fat into cups
• B. To weigh fat on a scale
• C. To measure solid fats by displacement of water
• D. To measure liquids by displacement

Answer: (C)

Displacement method uses the idea that a solid’s volume equals the amount of water it pushes aside when submerged. Plastic fats are solids with irregular shapes, so you can’t rely on geometry or packing to know their volume. By filling a graduated cylinder with a known amount of water, fully submerging the fat, and measuring the new water level, the difference gives the fat’s volume. This provides an accurate volume for solid fats regardless of shape. The other options don’t fit because packing into cups doesn’t measure volume by displacement, weighing gives mass, and displacement here is specifically for determining the volume of a solid rather than a liquid.