States & mixtures
Boiling point — স্ফুটনাঙ্ক
Quick answer
The temperature at which a liquid boils throughout; water boils at 100 °C at sea level, cooler on a high hill.
Definition
The boiling point is the temperature at which a liquid boils throughout: vapour bubbles form inside the liquid and rise, and the vapour pressure equals the air pressure above. Like melting, boiling keeps temperature steady while it happens — a boiling pot of water stays near 100 °C however high the flame, because extra heat goes into evaporation. Lower air pressure lowers the boiling point, so water boils cooler on a high hill.
For example
Rocket fuel tanks carry hydrogen and oxygen as liquids chilled to about −253 °C and −183 °C, their boiling points; that is how so much gas fits into a tank.