Answer:
The label on the X-axis is Heat Supplied or Absorbed
The label on the Y-axis is Temperature
Explanation:
The given graph is the heating curve of a substance as it is absorbs heat (increase in the x-axis) and have an increase in temperature (increase in the y-axis) between its different phases, from A to E
Therefore;
The label on the X-axis should be Heat Supplied or Absorbed
The label on the Y-axis should be Temperature
An appropriate state of phase 'A' is the solid phase of the substance where the temperature of the substance increases as heat is supplied without the substance changing into a liquid
Stage 'B' is the melting stage, when the substance transforms from solid to liquid as heat is applied, without an increase in temperature, which is seen by the horizontal line of stage 'B'
At stage 'C', the substance which is entirely liquid continues to absorb heat (moving to the right), while the temperature rises
At stage 'D', the substance in the liquid state continues to absorb heat (moving to the right), but rather than increase in its temperature, the substance transforms to the gaseous phase, which is phase 'E'
At phase 'E', the substance continue to absorb heat without changing state and therefore its temperature increases
The phases 'B', and 'D', where there is no increase in temperature as heat is added (progression to the right) are the regions where we have the latent heat of fusion and evaporation respectively.