Which of the following must be added to increase the temperature of steam at 110 °C?

• A. Ice
• B. Water
• C. Pressure
• D. Heat energy

Answer: (D)

Verified step by step guidance

1. Understand that temperature increase in a substance requires adding energy in the form of heat, which raises the kinetic energy of the molecules.
2. Recognize that adding ice or water at lower temperatures will not increase the temperature of steam; instead, they would absorb heat and potentially lower the steam's temperature.
3. Know that increasing pressure alone does not necessarily increase the temperature of steam unless it leads to compression and heating, but in this context, pressure is not the direct factor to raise temperature.
4. Recall the first law of thermodynamics, which states that to increase the temperature of a system, you must add heat energy to it.
5. Conclude that the correct way to increase the temperature of steam at 110 °C is to add heat energy, which directly increases the thermal energy and temperature of the steam.