Question

For the phase diagram of water given in figure, curves $OA,AB$ and $AC$ are respectively

• A. sublimation curve, vaporisation curve and fusion curve
• B. sublimation curve, fusion curve and vaporisation curve
• C. fusion curve, vaporisation curve and sublimation curve
• D. fusion curve, sublimation curve and vaporisation curve

Answer 1

Answer: (B)

The point on the sublimation curve $OA$ represents states in which the solid and vapour phases co-exist. Points on the fusion curve $AB$ represents states in which solid and liquid phase co-exist.
Points on the vaporisation curve $AC$ represents states in which the liquid and vapour phases co-exist.
Therefore, in the given graph, the curves $OA,AB$ and $AC$ are respectively sublimation curve, fusion curve and vaporisation curve.