Subject :NSO Class : Class 9
The given graph represents the cooling curve of substance X. Which of the following statements are incorrect?
I. Process I represents cooling of liquid state of X while process III involves cooling of the solid state.
II. The freezing point of substance X is 25 °C.
III. At 35 °C, the substance exists in solid state.
IV. Substance X exists both in gaseous and liquid form along the curve QR.
AI and III only
BII and IV only
CIII and IV only
DNone of these