Question

How can we directly change solid state into gaseous state without changing it into the intermediate state that is liquid state and reverse of it that is gaseous state into solid state directly?

Answer 1

Dear Student

Under certain conditions of temperature and pressure, solid change to gas directly and vice versa.
At temperatures below that of triple point, a decrease in pressure will result in a phase transition directly from the solid to the gaseous.
At pressures below the triple point pressure, an increase in temperature will result in a solid being converted to gas.
Water vapour transforms directly into ice, this process often occurs during winter months when temperature is very low.

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