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What is the Van't Hoff factor?
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The Van't Hoff factor (i) is the ratio of the observed colligative property to the calculated colligative property and is used to account for solute dissociation or association.
How does the observed vapor pressure compare to the theoretical vapor pressure for non-ideal solutions with positive deviation?
For non-ideal solutions with positive deviation: \(P_{observed} > P_{theoretical}\)
What happens to the boiling point of a solution when a non-volatile solute is added?
The boiling point of the solution increases.
What colligative property is the ratio of lowering of vapor pressure to the original vapor pressure?
Relative lowering of vapor pressure.
How do you calculate osmotic pressure with the Van't Hoff factor included?
\(\pi = i \cdot C \cdot R \cdot T\)
Provide an example of a non-ideal solution with negative deviation.
Chloroform and acetone
Define an ideal solution.
An ideal solution is one that obeys Raoult's law for all compositions and has all interactions (A-A, B-B, A-B) as identical.
What are the conditions for an ideal solution regarding enthalpy and volume of mixing?
For an ideal solution: \(\Delta H_{mixing} = 0\) and \(\Delta V_{mixing} = 0\)
What type of interactions lead to positive deviation in non-ideal solutions?
Positive deviation occurs when interactions between different molecules (A-B) are weaker than those between like molecules (A-A or B-B).
How do you calculate the Van't Hoff factor for a dissociating solute?
For a dissociating solute: \(i = 1 + (n - 1)\alpha\)
What is the formula for the elevation of boiling point?
\(\Delta T_b = K_b \cdot m\)
What is the formula for osmotic pressure?
\(\pi = C \cdot R \cdot T\)
What is the formula for depression of freezing point?
\(\Delta T_f = K_f \cdot m\)
What are the four main colligative properties?
Relative lowering of vapor pressure, elevation of boiling point, depression of freezing point, and osmotic pressure.
How is the relative lowering of vapor pressure defined for dilute solutions?
For dilute solutions, the relative lowering of vapor pressure is given by: \(\frac{P^0_A - P_s}{P^0_A} = \chi_B \)
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