Basic Concepts of Chemistry

Atoms: Basic unit of matter; composed of protons, neutrons, and electrons.
Molecules: Two or more atoms chemically bonded together.
Elements: Pure substances that cannot be broken down (e.g., hydrogen, oxygen).
Compounds: Substances formed when two or more elements are chemically combined (e.g., water, CO2).

Solid: Definite shape and volume; particles are closely packed.
Liquid: Definite volume but takes the shape of its container; particles are less tightly packed.
Gas: No definite shape or volume; particles are far apart and move freely.
Plasma: High-energy state where electrons are stripped from atoms; found in stars.

Ionic Bonds: Formed when electrons are transferred from one atom to another; creates charged ions.
Covalent Bonds: Formed when atoms share electrons; can be single, double, or triple bonds.
Metallic Bonds: Involves pooling of electrons among a lattice of metal atoms.

Reactants: Substances that undergo change during a reaction.
Products: Substances formed as a result of a chemical reaction.
Types of Reactions:
1. Synthesis: Two or more substances combine to form a new compound.
2. Decomposition: A single compound breaks down into two or more products.
3. Single Replacement: One element replaces another in a compound.
4. Double Replacement: Exchange of ions between two compounds.
5. Combustion: Reaction with oxygen, producing heat and light.

Acids: Substances that donate protons (H+) in a solution; taste sour, turn litmus red.
Bases: Substances that accept protons; taste bitter, slippery feel, turn litmus blue.
pH Scale: Measures acidity or basicity; ranges from 0 (acidic) to 14 (basic), with 7 being neutral.

Groups: Vertical columns; elements in the same group have similar chemical properties.
Periods: Horizontal rows; properties change progressively across a period.
Metals, Nonmetals, and Metalloids: Metals are good conductors; nonmetals are poor conductors; metalloids have properties of both.

Mole Concept: A mole is 6.022 x 10^23 particles of a substance.
Balanced Equations: Must have the same number of each type of atom on both sides.
Conversions: Use molar mass to convert between grams and moles.

Exothermic Reactions: Release heat; products have lower energy than reactants.
Endothermic Reactions: Absorb heat; products have higher energy than reactants.
Enthalpy (ΔH): Heat content of a system at constant pressure.

Hydrocarbons: Compounds composed entirely of hydrogen and carbon; can be aliphatic (straight or branched chains) or aromatic (ring structures).
Functional Groups: Specific groups of atoms that determine the chemical reactivity of molecules (e.g., alcohols, acids, amines).

Salts: Ionic compounds formed from the neutralization of an acid and a base.
Coordination Compounds: Complexes containing a central metal atom bonded to molecules or ions called ligands.

Personal Protective Equipment (PPE): Goggles, gloves, lab coats to avoid exposure to chemicals.
Chemical Storage: Proper labeling and separation of incompatible substances.
Emergency Procedures: Know exits, showers, eyewash stations, and fire extinguishers locations.

Atoms are the fundamental building blocks of matter, consisting of protons, neutrons, and electrons.
Molecules are formed when two or more atoms bond chemically.
Elements are pure substances that cannot be further broken down and include examples like hydrogen and oxygen.
Compounds result from the chemical combination of two or more different elements, such as water (H2O) and carbon dioxide (CO2).

Solids have a fixed shape and volume; their particles are tightly packed and vibrate in place.
Liquids have a definite volume but assume the shape of their container, with particles that are loosely packed and able to move around.
Gases lack both definite shape and volume, with widely spaced particles that move freely.
Plasma is a high-energy state of matter where electrons detach from atoms, commonly found in stars.

Ionic bonds occur when one atom transfers electrons to another, resulting in charged ions that attract each other.
Covalent bonds form through the sharing of electrons between atoms, which can vary in strength (single, double, or triple bonds).
Metallic bonds consist of a shared pool of electrons among a group of metal atoms, contributing to conductivity.

Reactants are the starting materials that undergo transformation during a chemical reaction.
Products are the end materials produced as a result of a reaction.
Types of chemical reactions include:
- Synthesis: Combining multiple reactants into one product.
- Decomposition: Breaking down one compound into multiple products.
- Single Replacement: An element substitutes for another in a compound.
- Double Replacement: An exchange of ions occurs between two compounds.
- Combustion: A reaction with oxygen, releasing heat and light.

Acids are substances that release protons (H+) in solution, characterized by a sour taste and a red litmus test.
Bases accept protons, are bitter, slippery, and turn litmus blue.
The pH scale measures acidity and basicity, ranging from 0 (acidic) to 14 (basic) with 7 as neutral.

Groups are vertical columns composed of elements with similar chemical properties.
Periods are horizontal rows where properties of elements shift gradually.
Metals are efficient conductors of heat and electricity, nonmetals are poor conductors, and metalloids have mixed properties.

A mole is defined as 6.022 x 10^23 particles of any substance.
Balanced chemical equations require an equal number of each type of atom on both reactant and product sides.
Conversions between grams and moles utilize molar mass as a key factor.

Exothermic reactions release heat, leading products to have lower energy than reactants.
Endothermic reactions absorb heat, thus, products possess higher energy than the starting materials.
Enthalpy (ΔH) describes the heat content of a system maintained at constant pressure.

Hydrocarbons consist solely of hydrogen and carbon and can be classified as aliphatic (linear or branched) or aromatic (circular).
Functional groups are specific groups of atoms that drive the reactivity of organic molecules, examples include alcohols, acids, and amines.

Salts are ionic compounds created through the neutralization of acids and bases.
Coordination compounds involve a central metal atom bonded to surrounding ligands, which can be molecules or ions.

Personal Protective Equipment (PPE) includes goggles, gloves, and lab coats to prevent chemical exposure.
Proper chemical storage involves labeling and keeping incompatible substances separate to avoid hazardous reactions.
Familiarity with emergency procedures is vital, including locations of exits, showers, eyewash stations, and fire extinguishers.