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15 g of an unknown molecular substance w...

15 g of an unknown molecular substance was dissolved in 450 g of water. The resulting solution freezes at - `0.34^(@)`C. what is molar mass of the substance ? `(K_(f)" for water " = 1.86 k kg " mol"^(-1))`

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(b) `W_(B)=15g W_(A)= 450 g, DeltaT_(f)= 34 K M_(B)`=?
`M_(B)= (1000xxK_(f)xxW_(B))/(DeltaT_(f)xxW_(A))`
`=(1000xx1.86"K mol"^(-1)xx15g)/(0.34xx450g)`
=182.35 g/ mol
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