Chemistry Chapter: Atomic Structure and Bonding

Atomic Structure

• Atoms are the fundamental building blocks of matter, composed of a nucleus containing protons and neutrons, surrounded by electrons.
• Protons carry a positive charge, neutrons are neutral, and electrons carry a negative charge.
• The number of protons determines the element's identity (atomic number).
• Atomic mass is the sum of protons and neutrons.
• Electrons orbit the nucleus in specific energy levels (shells) or orbitals.
• Electrons in the outermost shell (valence electrons) are involved in chemical bonding.
• Isotopes are atoms of the same element with different numbers of neutrons.

Bonding

• Chemical bonds hold atoms together in molecules or compounds.
• Ionic bonds form between a metal and a nonmetal, where one atom transfers electrons to another, creating oppositely charged ions.
• Covalent bonds form between nonmetals, where atoms share electrons.
• Metallic bonds form between metal atoms, where electrons are delocalized and shared throughout the structure.
• Hydrogen bonds are a special type of dipole-dipole interaction between a hydrogen atom bonded to a highly electronegative atom (like oxygen or nitrogen) and another electronegative atom.

States of Matter

• Matter exists in three primary states: solid, liquid, and gas.
• Solids have a fixed shape and volume due to strong intermolecular forces.
• Liquids have a fixed volume but take the shape of their container due to weaker intermolecular forces compared to solids.
• Gases have neither a fixed shape nor volume; they expand to fill their container due to very weak intermolecular forces.
• Plasma is a state of matter where electrons are stripped from atoms, resulting in a highly ionized gas.

Chemical Reactions

• Chemical reactions involve the rearrangement of atoms to form new substances.
• Reactants are the substances that undergo change, and products are the substances formed.
• Chemical equations represent reactions, showing the reactants and products.
• Reactions often involve energy changes (exothermic or endothermic).
• Balanced equations show that the number of atoms of each element is equal on both sides of the equation.

Periodic Table

• The periodic table organizes elements by increasing atomic number.
• Elements with similar properties are grouped in columns (groups or families).
• Elements are arranged in rows (periods) reflecting the electronic configuration.
• Metals, nonmetals, and metalloids are categorized based on their properties. Metals are typically good conductors of heat and electricity, while nonmetals are generally poor conductors.

Solutions

• Solutions are homogeneous mixtures of two or more substances.
• The solute is the substance dissolved, and the solvent is the substance doing the dissolving.
• Concentration describes the amount of solute in a given amount of solvent or solution.
• Solubility is the maximum amount of solute that can dissolve in a given amount of solvent at a given temperature.
• Different solutes have different solubilities in different solvents. Polar solvents typically dissolve polar solutes and nonpolar solvents dissolve nonpolar solutes.

Acids and Bases

• Acids are substances that release hydrogen ions (H+) in solution.
• Bases are substances that release hydroxide ions (OH-) in solution.
• The pH scale measures the acidity or basicity of a solution.
• A neutral solution has a pH of 7.
• Acids have a pH below 7, and bases have a pH above 7.

Stoichiometry

• Stoichiometry is the quantitative relationship between reactants and products in a chemical reaction.
• Mole ratios are used to determine the amounts of reactants and products in a reaction.
• Calculations use molar mass and mole ratios to relate quantities of reactants and products.

Redox Reactions

• Redox reactions involve the transfer of electrons between reactants.
• Oxidation is the loss of electrons, and reduction is the gain of electrons.
• Oxidation and reduction always occur together in a redox reaction.
• Oxidizing agents cause oxidation in other substances.
• Reducing agents cause reduction in other substances.

Test your knowledge on atomic structure and chemical bonding concepts. This quiz covers the basics of atoms, including protons, neutrons, electrons, and various types of chemical bonds. Understand the differences between ionic, covalent, and metallic bonds as well as the role of valence electrons.