Question

Why boiling point of water is lower at top of a mountain?

Answer 1

as we go higher and higher the pressure becomes lower and lower. As a result, boiling point of water is lower at the top of a mountain.

Answer 2

On the top of the mountains pressure is much lower than what is in ground level.{on going up pressure decrease}

$\underline{\blue{\large{Boiling\:point\:increases\:with\:increase\:in\:pressure\:and\:vice-versa}}}$.

$\red{ Since\: a\: liquid\: vaporises \:when\: molecules \:moves\: faster\: and \:farther\: apart\: but\: while\: increasing \:pressure,\: you\: are \:applying\: an\: external \:force\: to \:hold \:molecules\: closer\: to\: each \:other.\: Hence,\: molecules\: will \:require\: more \:energy\: to\: overcome\: this\: resistance\: thus\: this\: increases\: boiling\: point\: of\: liquid.}$