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At 25^(@)C , the saturated vapour pressure of water is 3.165 k Pa (23.75 mm Hg). Find the saturated vapour pressure of a 5% aqueous solution of urea (carbamide) at the same temperature. (Molar mass of urea = 60.05 g mol^(-1) ) |
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Answer» Solution :`(P^(0)- P_(S))/(P^(0)) = n_(2) = (n_(2))/(n)` (for DILUTE solution`n_(2) ltlt n_(1)`) `(P^(0) - P_(S))/(P^(0)) = (W_(2) xx M_(1))/(W_(1) xx M_(2))` GIVEN `P^(0)` = 3.165 kPa, `W_(2) = 5 g, W_(1) = 95 ` g `M_(2) = 60.05 g "mol"^(-1), M_(1) = 18 g mol^(-1)` `(3.165 - P_(s))/(3.165) = (5 xx 18)/(60.05 xx 95) = 0.0158` 3.165` - P_(s) ` = 0.049 `P_(s) = ` 3.116 kPa |
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