Basic Concepts in Chemistry

Matter: Anything that has mass and occupies space. Exists in three states: solid, liquid, gas.
Elements: Pure substances that cannot be broken down into simpler substances. Represented by symbols (e.g., H for hydrogen).
Compounds: Substances formed from two or more elements chemically bonded together (e.g., water, H2O).

Atoms: Smallest units of matter, consisting of protons, neutrons, and electrons.
- Protons: Positively charged particles located in the nucleus.
- Neutrons: Neutral particles also in the nucleus.
- Electrons: Negatively charged particles orbiting the nucleus in energy levels.
Atomic Number: Number of protons in an atom, determines the element.
Mass Number: Total number of protons and neutrons in the nucleus.

Ionic Bonds: Formed when electrons are transferred from one atom to another, creating charged ions.
Covalent Bonds: Formed when atoms share electrons to achieve stability.
Metallic Bonds: Bonding between metal atoms, characterized by a sea of delocalized electrons.

Reactants: Substances that undergo a change in a chemical reaction.
Products: New substances formed as a result of a chemical reaction.
Types of Reactions:
- Synthesis: Two or more reactants combine to form a single product.
- Decomposition: A single compound breaks down into two or more products.
- Single Replacement: An element replaces another element in a compound.
- Double Replacement: Exchange of ions between two compounds.
- Combustion: Reaction involving oxygen, producing heat and light (usually involves hydrocarbons).

Groups: Vertical columns indicating elements with similar properties (e.g., alkali metals, halogens).
Periods: Horizontal rows indicating increasing atomic number.
Metals, Nonmetals, and Metalloids: Distinct categories of elements based on physical and chemical properties.

Acids: Substances that donate protons (H+) in a solution; typically have a sour taste.
Bases: Substances that accept protons; typically feel slippery and taste bitter.
pH Scale: Measures the acidity or basicity of a solution (scale of 0-14; 7 is neutral).

Mole: A unit representing 6.022 x 10^23 particles (atoms, molecules).
Molar Mass: Mass of one mole of a substance, measured in grams per mole.
Balanced Chemical Equations: Represent the conservation of mass, where the number of atoms for each element is equal on both sides.

Exothermic Reactions: Release heat energy to the surroundings (e.g., combustion).
Endothermic Reactions: Absorb heat energy from the surroundings.

Hydrocarbons: Compounds consisting solely of hydrogen and carbon.
- Alkanes: Saturated hydrocarbons with single bonds.
- Alkenes: Unsaturated hydrocarbons with at least one double bond.
- Alkynes: Unsaturated hydrocarbons with at least one triple bond.
Functional Groups: Specific groups of atoms that determine the chemical properties of organic compounds (e.g., hydroxyl, carboxyl).

Focuses on compounds that are not covered by organic chemistry, including metals, minerals, and organometallic compounds.

Personal Protective Equipment (PPE): Use safety goggles, gloves, and lab coats when handling chemicals.
Emergency Procedures: Know the location of safety showers, eyewash stations, and fire extinguishers.

These notes provide a foundational overview of key concepts in chemistry, suitable for study or review.

Matter refers to anything possessing mass and occupying space, found in three states: solid, liquid, and gas.
Elements are pure substances that cannot be further simplified, represented by unique symbols (e.g., H for hydrogen).
Compounds consist of two or more elements chemically bonded, such as water (H2O).

Atoms are the smallest units of matter, made up of protons, neutrons, and electrons.
Protons have a positive charge and reside in the nucleus of an atom.
Neutrons are neutral particles located alongside protons in the nucleus.
Electrons carry a negative charge and orbit the nucleus within defined energy levels.
The atomic number represents the number of protons in an atom, determining its identity as an element.
Mass number is the sum of protons and neutrons in the nucleus.

Ionic bonds form through the transfer of electrons between atoms, leading to the creation of charged ions.
Covalent bonds arise from the sharing of electrons between atoms, promoting stability.
Metallic bonds involve a collection of metal atoms sharing delocalized electrons.

Reactants are the initial substances that undergo transformation during a reaction.
Products are the new substances produced as a result of a chemical reaction.
Types of reactions include:
- Synthesis: Combining multiple reactants into one product.
- Decomposition: Breaking down a single compound into two or more products.
- Single Replacement: One element displaces another in a compound.
- Double Replacement: Ions are exchanged between two compounds.
- Combustion: A reaction with oxygen, producing heat and light, typically involving hydrocarbons.

Groups represent vertical columns of elements with similar properties, such as alkali metals and halogens.
Periods are horizontal rows indicating elements arranged by increasing atomic number.
Elements are categorized into metals, nonmetals, and metalloids based on their physical and chemical characteristics.

Acids donate protons (H+) in solutions and generally have a sour taste.
Bases accept protons and typically feel slippery with a bitter taste.
The pH scale quantifies the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic), with 7 being neutral.

A mole represents 6.022 x 10^23 particles, whether atoms or molecules.
Molar mass is the weight of one mole of a substance, expressed in grams per mole.
Balanced chemical equations reflect mass conservation, ensuring equal numbers of atoms for each element on both sides of the equation.

Exothermic reactions emit heat energy to the surroundings, exemplified by combustion processes.
Endothermic reactions absorb heat energy from their environment.

Hydrocarbons are compounds composed solely of hydrogen and carbon atoms.
Alkanes are saturated hydrocarbons featuring only single bonds.
Alkenes contain at least one double bond, marking them as unsaturated hydrocarbons.
Alkynes are unsaturated hydrocarbons that possess at least one triple bond.
Functional groups are specific atom clusters that define the chemical properties of organic molecules, such as hydroxyl and carboxyl groups.

Focuses on chemical compounds not classified as organic, including various metals, minerals, and organometallic substances.

Personal Protective Equipment (PPE) is essential for safety, including goggles, gloves, and lab coats when handling chemicals.
Familiarity with emergency procedures is crucial, such as the locations of safety showers, eyewash stations, and fire extinguishers.