Respuesta :
Depression of a freezing point of the solutions depends on the number of particles of the solute in the solution.
1 mol of C6H12O6 after dissolving in water still be 1 mol, because C6H12O6 does no dissociate in water.
1 mol of C2H5OH after dissolving in water still be 1 mol, because C2H5OH does no dissociate in water.
1 mol of NaCl after dissolving in water gives 2 mol of particles (ions), because NaCl is a strong electrolyte(as salt) and completely dissociates in water.
NaCl ----->Na⁺ + Cl⁻
1 mol of CH3COOH after dissolving in water gives more than 1 mol but less than 2 moles, because CH3COOH is a weak electrolyte (weak acid) and dissociates only partially.
So, most particles of the solute is going to be in the solution of NaCl,
so the lowest freezing point has the aqueous solution of NaCl.
1 mol of C6H12O6 after dissolving in water still be 1 mol, because C6H12O6 does no dissociate in water.
1 mol of C2H5OH after dissolving in water still be 1 mol, because C2H5OH does no dissociate in water.
1 mol of NaCl after dissolving in water gives 2 mol of particles (ions), because NaCl is a strong electrolyte(as salt) and completely dissociates in water.
NaCl ----->Na⁺ + Cl⁻
1 mol of CH3COOH after dissolving in water gives more than 1 mol but less than 2 moles, because CH3COOH is a weak electrolyte (weak acid) and dissociates only partially.
So, most particles of the solute is going to be in the solution of NaCl,
so the lowest freezing point has the aqueous solution of NaCl.
Among C₆H₁₂O₆, C₂H₅OH, CH₃COOH, and NaCl, NaCl is the one that will provide the aqueous solution with the lowest freezing point.
We have 4 aqueous solutions and we want to determine which has the lowest freezing point.
- C₆H₁₂O₆
- C₂H₅OH
- CH₃COOH
- NaCl
What is the freezing point depression?
Freezing-point depression is a drop in the temperature at which a substance freezes, caused when a smaller amount of another, non-volatile substance is added.
We can calculate the freezing point depression (ΔT) using the following expression.
ΔT = Kf × b × i
where,
- Kf is the cryoscopic constant for water.
- b is the molality of the solution.
- i is the Van't Hoff factor.
Assuming all the solutions have the same molality, the freezing point depression will be a function of the van't Hoff factor.
What is the van't Hoff factor?
The van 't Hoff factor is the ratio between the actual concentration of particles produced when the substance is dissolved and the concentration of a substance as calculated from its mass.
- For non-electrolytes, such as C₆H₁₂O₆ and C₂H₅OH, i = 1.
- Comparing NaCl and CH₃COOH, we can determine that i(NaCl) > i(CH₃COOH) because NaCl is a strong electrolyte and CH₃COOH a weak one.
Thus, NaCl, with the highest Van't Hoff factor, will have the lowest freezing point.
Among C₆H₁₂O₆, C₂H₅OH, CH₃COOH, and NaCl, NaCl is the one that will provide the aqueous solution with the lowest freezing point.
Learn more about freezing point depression here: https://brainly.com/question/2292439
