Understanding Colligative Properties: Vapor Pressure Lowering

The video tutorial covers the concept of colligative properties, focusing on vapor pressure reduction. It explains how vapor pressure is defined and measured in saturated conditions. The tutorial discusses the effect of non-volatile solutes on vapor pressure, leading to a decrease in vapor pressure. Raoult's Law is introduced as a method to calculate vapor pressure changes, with a detailed example problem demonstrating the calculations. The video concludes with a summary of the key concepts and encourages viewers to like and subscribe.

What is the primary focus of the video tutorial?

• Chemical reactions

• Colligative properties

• Thermodynamics

• Atomic structure

What is vapor pressure?

• The pressure exerted by a vacuum

• The pressure exerted by a liquid

• The pressure exerted by a gas above a liquid

• The pressure exerted by solids

How does the presence of a non-volatile solute affect vapor pressure?

• Doubles the vapor pressure

• Has no effect on vapor pressure

• Decreases vapor pressure

• Increases vapor pressure

What does Raoult's Law relate to?

• The vapor pressure of a solution

• The density of a solution

• The freezing point of a solution

• The boiling point of a solution

According to Raoult's Law, what is vapor pressure proportional to?

• Temperature of the solution

• Volume of the solution

• Molarity of the solute

• Mole fraction of the solvent

In the example calculation, what is the solute used?

• Salt

• Sugar

• Glucose

• Ethanol

What is the molecular weight of glucose used in the example?

• 180

• 90

• 171

• 18

What is the initial vapor pressure of water in the example?

• 16.5 mm Hg

• 17 mm Hg

• 0.85 mm Hg

• 18 mm Hg

What is the calculated vapor pressure of the solution in the example?

• 17 mm Hg

• 18 mm Hg

• 16.5 mm Hg

• 0.85 mm Hg

What is the vapor pressure lowering in the example?

• 0.5 mm Hg

• 0.85 mm Hg

• 2.0 mm Hg

• 1.5 mm Hg