What are the colligative properties?

Question

Cameron Andrews · Accepted Answer

Colligative properties are those aspects of a solution's physical makeup that are determined by the particle concentration rather than type.

These characteristics include an increase in boiling point, a decrease in freezing point, a decrease in vapor pressure, and an increase in osmotic pressure.

Think about vapor pressure. Pure solvents with a tendency to evaporate more quickly show a higher vapor pressure than those without. Water has a lower vapor pressure than alcohols.

A solvent's vapor pressure decreases when solutes are added because they prevent the solvent from evaporating.

Water boils at a temperature greater than 100 degrees Celsius, so lowering the vapor pressure will cause the solvent to boil at a higher temperature. You can raise the boiling point of water by mixing it with table salt or sugar.

Water will freeze below zero degrees when solutes are added, and similarly, pure solvents will freeze at a lower temperature.

Because osmotic pressure is higher in solutions containing dissolved solutes than in pure solvents, salt increases blood vessel osmotic pressure, which is why it is harmful to those who have hypertension.

One last crucial idea to think about is which solute will increase the colliding aspect if the concentrations of electrolytes and non-electrolytes are equal. The electrolytes, of course.

If you dissolve 1.0 molal sucrose, #C_12H_22O_11# in water and compare the boiling point of this solution to 1.0 molal of NaCl, you find that table salt has greater effect on the elevation of the boiling point. Sucrose is a nonelectrolyte. Table salt, when dissolving in water, dissociates into two ions, sodium ion and chloride ion, which carry charges and therefore are electrolytes.

Dissociation causes the molal concentration to double; as a result, you have 2.0 molal of sodium ions and 1.0 molal of chloride ions.

I hope this clarification is useful.

Natalie Anton · Answer

undefined Colligative properties are properties of solutions that depend solely on the number of solute particles present, not on the identity of the solute particles. The four main colligative properties are vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.

Xavier Avery · Answer

undefined Colligative properties are properties of solutions that depend on the concentration of solute particles, regardless of their identity. The four main colligative properties are:

1. Vapor pressure lowering: The vapor pressure of a solvent decreases when solute particles are added, resulting in a lower vapor pressure compared to the pure solvent.

2. Boiling point elevation: The boiling point of a solution is higher than that of the pure solvent due to the presence of solute particles.

3. Freezing point depression: The freezing point of a solution is lower than that of the pure solvent because the presence of solute particles disrupts the formation of solvent crystals.

4. Osmotic pressure: The pressure required to stop the osmosis of solvent molecules across a semipermeable membrane from a region of lower solute concentration to a region of higher solute concentration.