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Questions and Answers
Which substance will cause the greatest boiling point elevation in a solution at a 1m concentration?
Which substance will cause the greatest boiling point elevation in a solution at a 1m concentration?
What is the primary factor affecting colligative properties of solutions?
What is the primary factor affecting colligative properties of solutions?
Which of the following correctly classifies NaCl and C6H12O6 in terms of their impact on colligative properties?
Which of the following correctly classifies NaCl and C6H12O6 in terms of their impact on colligative properties?
How do ionic compounds like CaCl2 affect the number of solute particles in a solution compared to molecular compounds?
How do ionic compounds like CaCl2 affect the number of solute particles in a solution compared to molecular compounds?
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If 1m solutions of NaCl and C6H12O6 are compared, which property will be more affected by NaCl's dissociation?
If 1m solutions of NaCl and C6H12O6 are compared, which property will be more affected by NaCl's dissociation?
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Which of the following statements about colligative properties is true?
Which of the following statements about colligative properties is true?
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Which pair of substances, when dissolved in water, will exhibit the least freezing point depression at the same molality?
Which pair of substances, when dissolved in water, will exhibit the least freezing point depression at the same molality?
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In assessing the effects of solutes on colligative properties, how are electrolytes different from non-electrolytes?
In assessing the effects of solutes on colligative properties, how are electrolytes different from non-electrolytes?
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What mainly determines the colligative properties of a solution?
What mainly determines the colligative properties of a solution?
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What is the formula for calculating molality?
What is the formula for calculating molality?
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Which statement correctly describes why adding salt to boiling water increases its temperature?
Which statement correctly describes why adding salt to boiling water increases its temperature?
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How much does the boiling point of water increase when 5 g of C12H22O11 is added?
How much does the boiling point of water increase when 5 g of C12H22O11 is added?
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What happens to the melting point of water when salts are added?
What happens to the melting point of water when salts are added?
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What is the boiling point of the solution when 85.0 g of Sodium acetate is dissolved in 356 mL of water?
What is the boiling point of the solution when 85.0 g of Sodium acetate is dissolved in 356 mL of water?
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What type of solution does NOT dissociate into ions when dissolved in a solvent?
What type of solution does NOT dissociate into ions when dissolved in a solvent?
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What is the effect of colligative properties on boiling point elevation?
What is the effect of colligative properties on boiling point elevation?
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What is the change in temperature (ΔTb) when 85.0 g of Sodium acetate is added to the solution?
What is the change in temperature (ΔTb) when 85.0 g of Sodium acetate is added to the solution?
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What condition is required for freezing point depression to occur?
What condition is required for freezing point depression to occur?
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In the context of nonelectrolyte and electrolyte solutions, the presence of more solute particles generally leads to which result?
In the context of nonelectrolyte and electrolyte solutions, the presence of more solute particles generally leads to which result?
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What relationship exists between molality and the freezing point depression?
What relationship exists between molality and the freezing point depression?
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Why do ice vendors add salt to the ice used in ice cream containers?
Why do ice vendors add salt to the ice used in ice cream containers?
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If 100 g of NaCl were added to 1 kg of water, what effect would it have on the boiling point of water?
If 100 g of NaCl were added to 1 kg of water, what effect would it have on the boiling point of water?
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The calculation of molar mass from colligative properties is primarily affected by which factor?
The calculation of molar mass from colligative properties is primarily affected by which factor?
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What is the boiling point constant (Kb) for water used in these calculations?
What is the boiling point constant (Kb) for water used in these calculations?
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What is the change in boiling point (ΔTb) when 15.0 g of an organic compound is dissolved in carbon tetrachloride resulting in a boiling point of 84.36°C?
What is the change in boiling point (ΔTb) when 15.0 g of an organic compound is dissolved in carbon tetrachloride resulting in a boiling point of 84.36°C?
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Using the boiling point elevation equation, if Kb for carbon tetrachloride is 5.02°C/m and the observed boiling point elevation is 7.64°C, what is the molality of the solution?
Using the boiling point elevation equation, if Kb for carbon tetrachloride is 5.02°C/m and the observed boiling point elevation is 7.64°C, what is the molality of the solution?
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How many moles of solute are present when 220 g of carbon tetrachloride is dissolved with a molality of 1.522 mol/kg?
How many moles of solute are present when 220 g of carbon tetrachloride is dissolved with a molality of 1.522 mol/kg?
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What is the molar mass of a solute if 15.00 g of it corresponds to 0.3348 moles?
What is the molar mass of a solute if 15.00 g of it corresponds to 0.3348 moles?
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How many grams of Pyrazine (C4H4N2) are needed to lower the freezing point of carbon tetrachloride by 5.6°C?
How many grams of Pyrazine (C4H4N2) are needed to lower the freezing point of carbon tetrachloride by 5.6°C?
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Given a molar mass of 80.0896 g/mol for Pyrazine, what is the total mass if 0.37 mol is to be dissolved?
Given a molar mass of 80.0896 g/mol for Pyrazine, what is the total mass if 0.37 mol is to be dissolved?
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If the freezing point depression constant (Kf) for carbon tetrachloride is 30.0°C/m, what is the relationship between freezing point depression and molality?
If the freezing point depression constant (Kf) for carbon tetrachloride is 30.0°C/m, what is the relationship between freezing point depression and molality?
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What substance is being dissolved in carbon tetrachloride in Sample Problem 2 to achieve freezing point depression?
What substance is being dissolved in carbon tetrachloride in Sample Problem 2 to achieve freezing point depression?
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What is the boiling point of the solution when 0.20 grams of eugenol is dissolved in 12.0 grams of benzene?
What is the boiling point of the solution when 0.20 grams of eugenol is dissolved in 12.0 grams of benzene?
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How does the freezing point of a solution containing benzoic acid compare to that of pure benzene?
How does the freezing point of a solution containing benzoic acid compare to that of pure benzene?
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What formula is used to calculate the boiling point elevation of a solution?
What formula is used to calculate the boiling point elevation of a solution?
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What is the molal freezing point depression constant (Kf) of water used for calculations?
What is the molal freezing point depression constant (Kf) of water used for calculations?
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In the freezing point depression calculations, which component is affected by the addition of the solute?
In the freezing point depression calculations, which component is affected by the addition of the solute?
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When calculating the molecular weight of a solute using freezing point depression, what information is required?
When calculating the molecular weight of a solute using freezing point depression, what information is required?
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What would be the effect on the boiling point of a solution when more solute is dissolved?
What would be the effect on the boiling point of a solution when more solute is dissolved?
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If 12g of glucose is dissolved in 200g of water, how much does the boiling point increase?
If 12g of glucose is dissolved in 200g of water, how much does the boiling point increase?
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Study Notes
Solutions Overview
- Solutions consist of solute (substance dissolved) and solvent (substance doing the dissolving).
- Properties of solutions, including colligative properties, depend on the amount of solute present.
- Colligative properties are influenced by the number of solute particles, not their identity.
Colligative Properties
- Colligative properties include boiling point elevation and freezing point depression.
- These properties demonstrate how adding a solute (like salt) changes boiling and freezing points of solvents.
- Example: Salt added to water raises its boiling point and lowers its freezing point.
Electrolyte vs. Nonelectrolyte
- Electrolytes (e.g., NaCl) dissociate into ions, increasing the number of particles in solution.
- Nonelectrolytes (e.g., sucrose) do not dissociate, resulting in fewer particles in the solution.
- The effect on boiling and freezing points is greater with electrolytes due to increased particle count.
Calculating Colligative Properties
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Molality (m) is calculated as the number of moles of solute per kilogram of solvent.
- Formula: Molality = moles of solute / kg of solvent
- Boiling point elevation (ΔTb) can be calculated using ΔTb = Kb x m.
- Freezing point depression and its relationship to the colligative properties are similar to boiling point calculations.
Example Calculations
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Boiling Point Elevation Example:
- For a solution with 5 g of sucrose in 180 g of water:
- Molality = 0.081 m, Kb for water = 0.512 °C/m
- ΔTb = Kb x m = 0.041 °C, resulting in a new boiling point of 100.041 °C.
- For a solution with 5 g of sucrose in 180 g of water:
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Freezing Point Depression Example:
- Adding a non-volatile solute lowers the vapor pressure and the freezing point.
- For a 15 g compound in 220 g carbon tetrachloride:
- ΔTb = 7.64 °C, leading to a molar mass of 44.80 g/mol after calculations.
Exercise Problems
- Practice involves solving for boiling points and freezing points with given constants and solute quantities.
- Activities include calculating specific scenarios such as the effects of different solutes on boiling and freezing points.
Assessments
- Students are tasked with determining molecular weights, boiling point elevations, and freezing point depressions through problem-solving scenarios.
- These problems reinforce understanding of colligative properties and their dependence on solute concentrations.
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Description
This quiz focuses on the concepts of nonelectrolyte and electrolyte solutions covered in General Chemistry 2 for grades 11 and 12. It is based on Module 5 from Quarter 3, helping students to understand the distinctions and applications of these types of solutions. Test your knowledge and prepare for your examinations!