20 g of fructose is being dissolved in 150g of H2O at 25°C.Calculate the boiling n freezing point of the solution.what is the osmotic pressure of the solution( density of water=100g/L)?
1 Answer
Apply the equations for colligative properties and osmotic pressure.
Explanation:
The change in boiling point will be
#DeltaT_b = i * b * K_b#
There is a similar equation for freezing point depression
#DeltaT_f = i * b * K_f#
osmotic pressure is
#prod = i * MRT#
The trick to solving this, is looking up the value of molal boiling point elevation constant for water, once you have that you need to calculate the molality (
It is useful to memorize the definition for molality
#"molality" = "moles of solute"/"kilograms of solvent"#
Look up the molar mass of fructose, calculate the number of moles, and then divide by 0.15 kg of
Fructose does not dissociate so
#T_b = 100 + DeltaTb#
You can go to a similar process to calculate the new freezing point, by using the freezing point equation (
Note the new freezing point will be
#T_f= 0 - DeltaT_f#
The formula for osmotic presure is slightly different, you need
#"molarity" = "moles of solute"/"liters of solution"#
Use the proper value of