끓는점오름. 4.01 kg water + 58 g NaCl

끓는점오름. 4.01 kg water + 58 g NaCl

 

 

George is making spaghetti for dinner.

He places 4.01 kg of water in a pan and brings it to a boil.

Before adding the pasta, he adds 58 g of table salt NaCl to the water

and again brings it to a boil.

The temperature of the salty, boiling water is _____ ℃?

Kb for water is 0.52 ℃/m.

 

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전해질 용액일 경우,

ΔTb = i × Kb × m

( 참고 https://ywpop.tistory.com/1920 )

 

 

 

100% 이온화 가정하면,

NaCl(aq) → Na^+(aq) + Cl^-(aq) ... i = 2

 

 

 

NaCl의 몰질량 = 58.44 g/mol

 

 

 

몰랄농도 = 용질 mol수 / 용매 kg수

= (58 / 58.44 mol) / 4.01 kg

= 0.2475 m

 

 

 

ΔTb = i × Kb × m

= (2) (0.52) (0.2475)

= 0.2574

= 0.26℃

 

 

 

물의 정상 끓는점 = 100℃ 이므로,

답: 100.26℃