Based on the phase diagram, the melting temperature of Q is 60°C, however the boiling temperature is not shown.
What is a phase diagram?
A phase diagram is a graph which shows the effect of pressure and temperature on the phase of a substance.
The melting or freezing point of a substance is that temperature in which the substance exists as both solid and liquid.
From the graph, the melting temperature of Q is 60°C.
The boiling or condensation point is temperature at which the substance exists as liquid and gas.
At the boiling point of a substance, its vapor pressure is equal to atmospheric pressure.
In the graph, the boiling temperature of Q is not shown clearly.
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