Atomic Structure and Chemical Bonding

Study Notes

Atomic Structure

Atoms are the fundamental building blocks of matter.
Atoms consist of a nucleus containing protons and neutrons, surrounded by orbiting electrons.
Protons are positively charged, neutrons are neutral, and electrons are negatively charged.
The number of protons in an atom's nucleus defines its atomic number and identifies the element.
Atomic mass is approximately the sum of protons and neutrons.
Isotopes are atoms of the same element with different numbers of neutrons.
Electron configuration describes the arrangement of electrons in atomic orbitals.
Quantum numbers define the properties of atomic orbitals and the electrons within them.

Chemical Bonding

Chemical bonds hold atoms together to form molecules and compounds.
Ionic bonding involves the transfer of electrons between atoms, forming ions with opposite charges that attract each other.
Covalent bonding involves the sharing of electrons between atoms.
Metallic bonding involves the sharing of electrons among many atoms in a metallic structure.
Intermolecular forces are forces of attraction between molecules.
- Dipole-dipole forces
- London dispersion forces
- Hydrogen bonds
Bond polarity arises from differences in electronegativity between atoms.
Electronegativity is the ability of an atom to attract electrons in a chemical bond.

States of Matter

Matter exists in solid, liquid, and gaseous states.
Solids have fixed volume and shape.
Liquids have fixed volume but take the shape of their container.
Gases have neither fixed volume nor shape and expand to fill their container.
Phase changes involve transitions between these states.
- Melting
- Freezing
- Vaporization
- Condensation
- Sublimation
- Deposition

Chemical Reactions

Chemical reactions involve the rearrangement of atoms to form new substances.
Reactants are the substances that undergo the change.
Products are the substances that are formed.
Chemical equations represent reactions using symbols and formulas.
Stoichiometry involves using balanced chemical equations to calculate quantities of reactants and products.
Types of reactions
- Synthesis
- Decomposition
- Single displacement
- Double displacement
- Combustion
Reaction rates depend on factors such as temperature, concentration, and surface area.

Acids and Bases

Acids are substances that release hydrogen ions (H+) in water.
Bases are substances that release hydroxide ions (OH-) in water.
The pH scale measures the acidity or basicity of a solution.
- pH values range from 0 to 14, with 7 being neutral
Strong acids and bases dissociate completely in water, while weak ones do not.
Neutralization reactions occur when an acid and a base react to form water and a salt.

Thermodynamics

Thermodynamics deals with energy changes in chemical and physical processes.
Enthalpy (ΔH) measures the heat content of a system under constant pressure.
Entropy (ΔS) measures the disorder or randomness of a system.
Gibbs free energy (ΔG) relates enthalpy and entropy to predict the spontaneity of a reaction.
Exothermic reactions release heat (ΔH is negative).
Endothermic reactions absorb heat (ΔH is positive).

Periodic Table

The periodic table organizes elements by atomic number and recurring chemical properties.
Elements in the same group (column) have similar properties.
Elements in the same period (row) display trends in properties across the table.
Atomic radii, electronegativity, and ionization energy show periodic trends.

Solutions

Solutions are homogeneous mixtures of two or more substances.
Solutes dissolve in solvents to form solutions.
Concentration measures the amount of solute in a given amount of solution.
Molarity (M) is a common unit of concentration.
Colligative properties depend on the concentration of solute particles, not their identity.
- Vapor pressure lowering
- Boiling point elevation
- Freezing point depression
- Osmosis

Description

This quiz covers the essential concepts of atomic structure and chemical bonding. You'll explore topics such as the composition of atoms, types of bonding, and the role of electrons. Perfect for chemistry students looking to test their understanding!