Question

The particles of an ice cube at 0°C (represented by the blue circles) come in contact with the particles of Juan’s hand at 37°C (represented by the orange circles). Which diagram correctly represents the temperature of the two substances and the direction of heat flow?

Answer 1

The correct diagram shows the orange (37°C) particles hotter than the blue (0°C) particles, with an arrow pointing from the orange to the blue.

Reason: heat flows from the warmer object (Juan’s hand at 37°C) to the colder object (ice at 0°C) until thermal equilibrium (or until the ice melts).