Unit 3: Properties of Substances & Mixtures

These flashcards cover essential concepts from Unit 3, focusing on the properties of substances, intermolecular forces, bonding types, and gas behaviors.

What are the two main types of forces that hold compounds and molecules together?

Intramolecular forces (within molecules) and intermolecular forces (between molecules).

What is the difference between covalent and ionic bonds?

Covalent bonds involve the sharing of electrons between nonmetals, while ionic bonds involve the transfer of electrons from metals to nonmetals.

Explain London Dispersion Forces.

London Dispersion Forces are the weakest intermolecular forces that occur between all molecules due to temporary dipoles caused by electron movement.

What is an induced dipole?

An induced dipole is a temporary dipole that occurs in a neighboring atom when a dipole from another atom influences the electron distribution.

How do the size of molecules affect London Dispersion Forces?

Larger molecules have larger partial charges, leading to stronger London Dispersion Forces.

What is a dipole-dipole interaction?

A dipole-dipole interaction occurs between polar molecules where the positive end of one molecule is attracted to the negative end of another.

What characterizes hydrogen bonding?

Hydrogen bonding is a strong type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like F, O, or N.

State the main properties of covalent network solids.

Covalent network solids are usually hard and brittle, have very high melting points, and do not conduct electricity.

What distinguishes ionic solids from other solid types?

Ionic solids are made up of charged ions held together by strong electrostatic forces, resulting in high melting points and brittleness.

Describe the characteristics of metallic solids.

Metallic solids are characterized by their ability to conduct electricity, malleability, ductility, and variable melting points.

What is the ideal gas law equation?

The ideal gas law equation is PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature.

Why do gases behave ideally at higher temperatures and lower pressures?

Gases behave ideally because they experience negligible intermolecular forces and occupy a larger volume compared to their particle volume.

What happens to real gases under high pressure and low temperature?

Real gases deviate from ideal behavior due to increased intermolecular attractions and significant particle volume.

How does temperature affect the average kinetic energy of gas particles?

The average kinetic energy of gas particles is directly proportional to the Kelvin temperature of the gas.

What is Maxwell-Boltzmann distribution?

Maxwell-Boltzmann distribution illustrates the range of speeds of gas particles at a certain temperature.

What happens to gas pressure as temperature increases in terms of Kinetic Molecular Theory?

As temperature increases, particles move faster, resulting in more frequent and stronger collisions with the container walls, increasing pressure.