22℃ 에틸렌 글라이콜 용액에서 물의 증기압. % ethylene glycol by mass = 39.0%

22℃ 에틸렌 글라이콜 용액에서 물의 증기압. % ethylene glycol by mass = 39.0%

순수한 물의 증기압 = 19.83 mmHg

 

 

Calculate the vapor pressure of water over each of the following ethylene glycol (C2H6O2) solutions at 22℃ (vp pure water = 19.83 mmHg).

Ethylene glycol can be assumed to be nonvolatile.

a) X_ethylene glycol = 0.288

b) % ethylene glycol by mass = 39.0%

c) 2.42 m ethylene glycol

 

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b) % ethylene glycol by mass = 39.0%

 

용액이 100 g 있다고 가정하면,

( 100 g 설명 https://ywpop.tistory.com/10963 )

 

> ethylene glycol의 질량 = 39.0 g

> 물의 질량 = 61.0 g

 

 

 

C2H6O2의 몰질량 = 62.07 g/mol

39.0 g / (62.07 g/mol) = 0.6283 mol ethylene glycol

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

H2O의 몰질량 = 18.02 g/mol

61.0 g / (18.02 g/mol) = 3.3851 mol H2O

 

 

 

H2O의 몰분율 = 3.3851 / (0.6283 + 3.3851) = 0.843

( 참고 https://ywpop.tistory.com/2659 )

 

 

 

P_용액 = X_용매 × P°_용매

( 참고 https://ywpop.tistory.com/2646 )

 

= (0.843) (19.83 mmHg)

= 16.72 mmHg

 

 

 

답: 16.7 mmHg

 

 

 

[키워드] 22℃ C2H6O2 19.83 mmHg % ethylene glycol by mass 39.0%