If K_b denotes the molal elevation constant o | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) The molality $m$ of the solution is calculated as follows:Mass of glucose $(W_2)$ $= 36 \ g$.Molar mass of glucose $(M_2)$ $= 180 \ g \ mol^{-1}$.

Vedclass · Accepted Answer

$(100 + \frac{2 \ K_b}{10})^{\circ} C$

Vedclass · Answer

(D) The molality $m$ of the solution is calculated as follows:Mass of glucose $(W_2)$ $= 36 \ g$.Molar mass of glucose $(M_2)$ $= 180 \ g \ mol^{-1}$.Volume of solution $= 1 \ dm^3 = 1 \ L$.Assuming the density of the solution is approximately $1 \ g \ mL^{-1}$,the mass of the solvent (water) $W_1$ is $1000 \ g = 1 \ kg$.Molality $m = \frac{W_2}{M_2 	imes W_1 (	ext{in } kg)} = \frac{36}{180 	imes 1} = 0.2 \ mol \ kg^{-1} = \frac{2}{10} \ mol \ kg^{-1}$.The elevation in boiling point is given by $\Delta T_b = K_b 	imes m = K_b 	imes \frac{2}{10} = \frac{2 \ K_b}{10}$.The boiling point of water is $100^{\circ} C$.Therefore,the boiling point of the solution $T_b = 100 + \Delta T_b = (100 + \frac{2 \ K_b}{10})^{\circ} C$.

If $K_b$ denotes the molal elevation constant of water,then the boiling point of an aqueous solution containing $36 \ g$ of glucose (molar mass $= 180 \ g \ mol^{-1}$) per $dm^3$ is:

Similar Questions

Calculate the molar mass of a non-volatile solute when $5 \ g$ of it is dissolved in $50 \ g$ of solvent,which boils at $119.6^{\circ} C$. $[K_{b} = 3.2 \ K \ kg \ mol^{-1}$,boiling point of pure solvent $= 118^{\circ} C]$.

$11.1 \ g$ of $CaCl_2$ is dissolved in $1 \ kg$ of water. Determine the elevation in boiling point of the solution. $[K_b = 0.5 \ K \ kg \ mol^{-1}]$ :-

Exactly $1 \ g$ of urea dissolved in $75 \ g$ of water gives a solution that boils at $100.114 \ ^oC$ at $760 \ torr$. The molecular weight of urea is $60.1$. The boiling point elevation constant for water is

Which of the following formulas correctly gives the value of the ebullioscopic constant $(K_{b})$?

An aqueous solution containing $1 \ g$ of urea boils at $100.25 \ ^oC$. The aqueous solution containing $3 \ g$ of glucose in the same volume will boil at ........ $^oC$. (Molecular weight of urea and glucose are $60$ and $180$ respectively)

Vedclass Test Series

Exam Paper Generator

Online Exam Module