Let the total
vapour pressure at this stage be ptotal and p1 and p2 be the partial
vapour pressures of the two components 1 and 2 respectively These
partial pressures are related to the mole fractions x1 and x2 of the two
components 1 and 2 respectively The French chemist, Francois Marte Raoult (1886) gave the
quantitative relationship between them The relationship is known as
the Raoult’s law which states that for a solution of volatile liquids,
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