(a) Define the following terms:
(i) Molarity
(ii) Molal elevation constant `(k_(b))`
(b) A solution containing 15 g (molar mass=60 g `mol^(-1))` per litre of solution water has the same osmotic pressure (isotonic ) as a solution of glucose (molar mass =180g `mol^(-1))` in water calculate the mass of glucose present in one litre of its solution.

Explanation

(a)(i) Molarity (M) : Molrity can be defined as no of moles of solute dissolved per liitre of solutiohn lolarity M= vol of solutio (liter moles of solute)
(ii) Molal elevation constant (kb) When 1 molal solution is prepared the elevation in boiling point is called as molal boling point elevation constant
(b) For isotonic solution
`pi_("urea")=("WBRT")/("MB"xxV)=(15 RT)/(60 V)`
`pi_("glucose")=("WBRT")/(180V)`
`pi_("urea")=pi_("glucose")`
`(15"RT")/(60 V)=("WBRT")/(180V)`
WB=`(15xx180)/(60)=45g`