증기압내림. 88.2 g of urea in 303 mL of water at 35℃

증기압내림. 88.2 g of urea in 303 mL of water at 35℃

 

 

Calculate the vapor pressure of a solution

made by dissolving 88.2 g of urea (molar mass = 60.06 g/mol)

in 303 mL of water at 35℃.

Vapor pressure of water at 35℃ is 42.18 mmHg.

 

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35℃ 물의 밀도 = 0.994 g/mL

303 mL × (0.994 g/mL) = 301.182 g H2O

 

 

 

301.182 g × (1 mol / 18.015 g) = 16.72 mol H2O

 

 

 

88.2 g × (1 mol / 60.06 g) = 1.469 mol urea

 

 

 

n_tot = 16.72 + 1.469 = 18.19 mol

 

 

 

X_H2O = 16.72 / 18.19 = 0.9192

( 참고: 몰분율 https://ywpop.tistory.com/2659 )

 

 

 

P_용매 = X_용매 × P°_용매

( 참고 https://ywpop.tistory.com/2646 )

= 0.9192 × 42.18 mmHg

= 38.77 mmHg

 

 

 

답: 38.8 mmHg

 

 

 

 

[키워드] 35℃ water 303 mL urea 88.2 g 42.18 mmHg