Question

a student has 25 grams of 20 °c water inside an insulated container with a lid. the student plans to collect evidence over two trials on thermal energy transfer by adding another substance to the container and then measuring the temperature after time has passed. which two materials will yield the best evidence of thermal energy transfer within the closed system? 25 grams of 0 °c ice 50 grams of 20 °c water 25 grams of 50 °c iron (fe) 50 grams of 20 °c iron (fe)

Explanation:

Step1: Understand thermal - energy transfer principle

Thermal energy transfers from high - temperature to low - temperature substances.

Step2: Analyze 25 grams of 0 °C ice

Since it is at 0 °C and the water is at 20 °C, heat will transfer from water to ice, causing ice to melt and temperature of water to drop.

Step3: Analyze 50 grams of 20 °C water

Same temperature as initial water, no net thermal energy transfer occurs.

Step4: Analyze 25 grams of 50 °C iron (Fe)

It is at a higher temperature than the water (20 °C), so heat will transfer from iron to water, changing the temperature of both substances.

Step5: Analyze 50 grams of 20 °C iron (Fe)

Same temperature as water, no net thermal energy transfer.

Answer:

• 25 grams of 0 °C ice
• 25 grams of 50 °C iron (Fe)