Vapor pressure of pure water at $298 K$ is $23.8 m m H g$ . $50 g$ of urea is dissolved in $850 g$ of water. Calculate the vapor pressure of water for this solution and it's relative lowering.

Open in App

Solution

$P_{A}^{o} = 23.8 M m H g; m_{H_{2} O} = 850 g m; m_{u r e a} = 50 g m$
Moles of $H_{2} O = 47.22 m o l e s$
Moles of Urea $= \frac{50}{60} = 0.833$
Mole fraction of $H_{2} O = \frac{47.22}{48.053} = 0.982$
Vapor pressure of water $=(mole fraction)×PoA$ (Raoults Law)
$P_{A} = 0.982 \times 23.8 = 23.37 m m H g$
Relative lowering $= \frac{P_{A}^{o} P_{A}}{P_{A}^{o}} = 0.018 m m H g$

Suggest Corrections

Similar questions

Q. Vapour pressure of pure water at

298 K

23.8 m m H g

50 g

of urea

(N H_{2} C O N H_{2})

is dissolved in

850 g

of water. Calculate the vapour pressure of water for this solution and its relative lowering.

Vapour pressure of pure water at 298 K is 23.8 mm Hg. 50 g of urea (NH₂CONH₂) is dissolved in 850 g of water. Calculate the vapour pressure of water for this solution and its relative lowering.

Q. Vapour pressure of pure water at

298 K

23.8 m m

H g

50 g

of urea is dissolved in

850 g

of water. The vapour pressure of water for this solution and its relative lowering are respectively:

30 g

of urea

(M = 60 g m o l^{- 1})

is dissolved in

846 g

of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at

298 K

23.8 m m H g

0.6 g

urea is added to

360 g

water. Calculate lowering in vapor pressure for this solution
(Given: Vapour pressure of

H_{2} O

35 m m

H g

)

Join BYJU'S Learning Program

Vapor pressure of pure water at 298 K is 23.8 mmHg. 50 g of urea is dissolved in 850 g of water. Calculate the vapor pressure of water for this solution and it's relative lowering.

PoA=23.8 Mm Hg; mH2O=850 gm; murea=50 gmMoles of H2O=47.22 molesMoles of Urea =5060=0.833Mole fraction of H2O=47.2248.053=0.982Vapor pressure of water =(mole fraction)×PoA(Raoults Law)PA=0.982×23.8=23.37 mm HgRelative lowering =PoAPAPoA=0.018 mm Hg

Vapor pressure of pure water at $298 K$ is $23.8 m m H g$ . $50 g$ of urea is dissolved in $850 g$ of water. Calculate the vapor pressure of water for this solution and it's relative lowering.