Question

Why in sublimation process solid directly convert into gas?

Answer 1

it is not directly converted ......
it is in liquid state for very short interval

Answer 2

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Sublimation is a process in which solid gets directly converted into gaseous state without going to the liquid state.
At pressures below the triple point pressure,an increase in temperature will result in a solid being converted to gaseous state without passing through the liquid state.

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