Quality of 100% corresponds to which statement about the steam?

• A. Dry, saturated steam
• B. Dry, superheated steam
• C. Wet steam
• D. Saturated liquid

Answer: (A)

Quality tells you how much of a saturated liquid–vapor mixture is vapor versus liquid. A quality of 1 (100%) means there is no liquid present—it's all vapor. That is dry, saturated steam, which sits on the saturated vapor line at the given pressure. If any liquid remains, it’s wet steam (0 < x < 1). If the vapor is heated above the saturation temperature at that pressure, it becomes superheated, where the concept of quality isn’t used. So 100% quality corresponds to dry, saturated steam.