Question

a researcher places a hot glass of water (100°c) and a cold metal block (10°c) in a closed system. which of the following statements are correct regarding the heat transfer process? a thermal energy will flow from the metal block to the glass of water. b thermal energy transfer between the metal block and the glass will continue (gain and lose) until therma c the metal block will eventually reach a temperature above 10°c. d the glass of water will remain at 100°c throughout the experiment.

Explanation:

Heat transfer occurs from a region of higher temperature to a region of lower temperature until thermal equilibrium is reached. Thermal equilibrium means there is no net heat transfer between the two objects and they have the same temperature.

• Option A: Thermal energy flows from the hotter object (glass of water at \(100^{\circ}C\)) to the colder object (metal block at \(10^{\circ}C\)), not from the metal block to the glass of water. So, this option is incorrect.
• Option B: Thermal energy transfer (gain and loss) continues until thermal equilibrium (same temperature) is achieved. This is in line with the principle of heat transfer.
• Option C: At thermal equilibrium, the metal block and the glass of water will have the same temperature. Since the initial temperatures are \(100^{\circ}C\) and \(10^{\circ}C\), the final temperature will be between \(10^{\circ}C\) and \(100^{\circ}C\), not above \(10^{\circ}C\) (it will be higher than \(10^{\circ}C\) but not just “above \(10^{\circ}C\)” in an unqualified way as the final temperature is determined by the heat - capacity and mass of both substances). So, this option is incorrect.
• Option D: The glass of water will lose heat (its temperature will decrease) until thermal equilibrium is reached. It will not remain at \(100^{\circ}C\) throughout the experiment. So, this option is incorrect.

Answer:

B. Thermal energy transfer between the metal block and the glass will continue (gain and lose) until thermal equilibrium.