Properties of Liquids

A series of flashcards to aid in reviewing key concepts in General Chemistry II, focusing on the properties and behaviors of liquids.

Intermolecular Forces

Forces of attraction or repulsion between molecules that influence the physical properties of liquids.

Surface Tension

The property of a liquid that causes it to behave as if it has an 'elastic skin' at its surface.

Vapor Pressure

The equilibrium pressure exerted by a vapor above its liquid in a closed container.

Viscosity

A measure of a fluid’s resistance to flow; describes the thickness of a liquid.

Cohesion

Intermolecular attraction between like molecules.

Adhesion

Attraction between unlike molecules.

Capillary Action

The tendency of a liquid to rise in narrow tubes due to intermolecular attraction.

Boiling Point

The temperature at which a liquid converts into a gas when its vapor pressure equals external pressure.

Molar Heat of Vaporization (ΔHvap)

The amount of heat required to vaporize one mole of a liquid at its boiling point.

Dynamic Viscosity

The measure of a fluid's internal resistance to flow under an applied force.

Kinematic Viscosity

The ratio of dynamic viscosity to fluid density.

Surface Tension Measurement

Typically measured in dynes/cm, the force required to break a film of length one cm.

Factors Affecting Surface Tension

Temperature, presence of solutes, and the strength of intermolecular forces.

Liquid Density

The mass per unit volume of a liquid, typically fixed and not easily compressed.

Hydrogen Bonding

Strong intermolecular attraction that significantly impacts water’s properties.

High Surface Tension

Occurs in liquids like water with strong intermolecular forces.

Vapor Pressure and Temperature

Increasing temperature raises vapor pressure by allowing more molecules to escape.

Example of Cohesion

Water beads forming on a leaf due to its cohesive properties.

Example of Adhesion

Water climbing up a paper towel due to adhesion between water and paper.

Factors Affecting Viscosity

Temperature, molecular size and shape, and pressure.

Examples of High Viscosity

Honey, molasses; liquids that are thick and flow slowly.

Examples of Low Viscosity

Water, ethanol; liquids that flow easily.

Normal Boiling Point of Water

100°C at 1 atm of pressure.

Effect of Pressure on Boiling Point

Lower pressure decreases boiling point; e.g., water boils at 82°C at 0.5 atm.

Vapor Pressure and Intermolecular Forces

Weaker intermolecular forces result in higher vapor pressure.

Molar Heat of Vaporization and Intermolecular Forces

Stronger forces lead to higher ΔHvap.

Surface Tension and Temperature

Increasing temperature decreases surface tension.

Capillary Action Example

Water moving through a narrow tube or being absorbed by a sponge.

Examples of Vapor Pressure

Perfume scent in the air; liquid boiling when its vapor pressure equals atmospheric pressure.

Relationship of Boiling Point to Molar Heat of Vaporization

Higher molar heat of vaporization correlates with higher boiling points.

Viscosity of Blood

Impacts cardiovascular health and flow in the circulatory system.

Impact of Surface Area on Vapor Pressure

Larger surface area increases evaporation rate, thus affecting vapor pressure.

Example of Surface Tension Effects

Water striders can walk on water due to surface tension.

Average Temperature Effect on Surface Tension

Higher average temperatures result in lower surface tension.

Liquid Behavior in a Closed Container

Equilibrium is established between liquid and its vapor.

Intermolecular Force Strength

The stronger the forces of attraction, the lower the vapor pressure.

Liquid Volume Behavior

Liquids have a fixed volume and fill the shape of their container.

Effect of Solutes on Surface Tension

Solutes like soap can decrease surface tension.

Example of Liquid with High Surface Tension

Mercury has a very high surface tension due to strong intermolecular forces.

Equilibrium Vapor Pressure Definition

The maximum vapor pressure at a given temperature.

Effect of Temperature on Viscosity

Higher temperatures decrease viscosity, making liquids flow easier.

Molecular Size Influence on Viscosity

Larger molecules generally lead to higher viscosity.

Temperature's Influence on Vapor Pressure

Higher temperatures result in higher vapor pressure as more molecules escape.

Example of Fluid Resistance to Flow

Motor oil’s viscosity affects engine performance.

Factors Influencing Capillary Action

Tube diameter, surface tension, and adhesive properties.