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प्रश्न
A solution of glucose (molar mass = 180 g mol–1) in water is labelled as 10% (by mass). What would be the molality and molarity of the solution ? (Density of solution = 1.2 g mL–1)
उत्तर
`"Molarity M"=(%"Mass"xx10xx"density")/"Mol. mass of solute"`
`=(10xx10xx1.2)/180= 0.66M`
`Molality=(%"Mass")/"Mol. mass of solute"xx1000/(100"-%Mass")`
`=10/180xx1000/90=0.617 m`
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