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What is the freezing point of an aqueous glucose solution that has 25.0 g of glucose?

User Antichris
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1 Answer

6 votes

Answer:


T_f=-2.58\°C

Step-by-step explanation:

Hello,

In this case, we can compute the the freezing point depression by using the following formula:


T_f-T_0=-i*m*Kf

Whereas the freezing point of pure water is 0 °C van't Hoff factor for glucose is 1, the molality is computed as shown below and the freezing point constant of water is 1.86 °C/m:


m=(25.0g\ glucose*(1mol\ glucose)/(180g\ glucose) )/(100g*(1kg)/(1000g) )\\ \\m=1.39m

Thus, the freezing point of the solution is:


T_f=T_0-i*m*Kf\\\\T_f=0\°C-1*1.39m*1.86(\°C)/(m)\\ \\T_f=-2.58\°C

Regards.

User Janielle
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