Question

two open containers and two closed containers with various levels of insulation are filled with 300 ml of 65°c hot chocolate. each container is placed on the same counter for one hour, and the temperature of the hot chocolate is checked at five - minute intervals. the data is recorded in the graph. comparing the efficiency of insulators according to the graph, which container was most effective in keeping the hot chocolate closest to the original temperature? a ceramic open container b silicon - lined with silicon lid c metal open container d ceramic with silicon lid

Explanation:

Step1: Understand the concept of insulation

A more effective insulator will keep the hot chocolate closer to its original temperature (higher temperature over time).

Step2: Analyze the graph

We look at the temperatures of each container over time. The container whose temperature - line is highest (closest to the original temperature of \(65^{\circ}C\)) at later times (e.g., around 60 minutes) is the most effective insulator.
Looking at the key:

• The solid - line for "Ceramic with Silicon lid" (Option D) is the highest among all the lines at later times.
• The "Metal open container" (Option C) will lose heat quickly (low temperature at later times).
• The "Ceramic open container" (Option A) loses more heat than the "Ceramic with Silicon lid" since it's open.
• The "Silicon - lined with silicon lid" (Option B) is not as high as the "Ceramic with Silicon lid" at later times.

Answer:

D. Ceramic with silicon lid