Is the question asking for the calculation of the van’t Hoff factor (i) for KBr at a given concentration, based on the provided osmotic pressure, correct?

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Identify the formula for osmotic pressure: \( \Pi = iMRT \), where \( \Pi \) is the osmotic pressure, \( i \) is the van’t Hoff factor, \( M \) is the molarity, \( R \) is the ideal gas constant, and \( T \) is the temperature in Kelvin.

Rearrange the formula to solve for the van’t Hoff factor \( i \): \( i = \frac{\Pi}{MRT} \).

Ensure you have all the necessary values: osmotic pressure (\( \Pi \)), molarity (\( M \)), the ideal gas constant (\( R \)), and temperature (\( T \)) in Kelvin.

Substitute the known values into the rearranged formula to calculate \( i \).

Interpret the calculated van’t Hoff factor \( i \) to understand the degree of dissociation of KBr in the solution.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

van't Hoff Factor (i)

The van't Hoff factor (i) is a dimensionless quantity that indicates the number of particles into which a solute dissociates in solution. For ionic compounds like KBr, which dissociates into K+ and Br-, the van't Hoff factor is 2. This factor is crucial for calculations involving colligative properties, such as osmotic pressure, as it affects the overall concentration of solute particles in solution.

Osmotic Pressure

Osmotic pressure is the pressure required to prevent the flow of solvent into a solution through a semipermeable membrane. It is directly proportional to the concentration of solute particles in the solution, as described by the formula π = iCRT, where π is osmotic pressure, i is the van't Hoff factor, C is the molar concentration, and R is the ideal gas constant. Understanding this relationship is essential for calculating osmotic pressure in solutions.

Colligative Properties

Colligative properties are properties of solutions that depend on the number of solute particles rather than their identity. These properties include boiling point elevation, freezing point depression, vapor pressure lowering, and osmotic pressure. The van't Hoff factor plays a significant role in these properties, as it quantifies the effective concentration of solute particles, influencing how these properties manifest in a solution.

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Colligative Properties

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