750.0 g water 1.25 mol CaCl2 525 g water 2.5 g C6H12O6

750.0 g water 1.25 mol CaCl2 525 g water 2.5 g C6H12O6

 

 

Calculate the molality of each of the following solutions:

a) 1.25 mol CaCl2 in 750.0 g water

b) 2.5 g C6H12O6 in 525 g water

c) 17.5 mL 2-propanol, (CH3)2CHOH (d = 0.785 g/mL)

in 35.5 mL H2O (d = 1.00 g/mL)

 

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몰랄농도 = 용질 mol수 / 용매 kg수

( 참고 https://ywpop.tistory.com/2667 )

 

 

 

a) 1.25 mol / (750.0/1000 kg)

= 1.67 mol/kg

 

 

 

b) C6H12O6의 몰질량 = 180.16 g/mol 이므로,

(2.5 g / (180.16 g/mol)) / (525/1000 kg)

= 0.026 mol/kg