Basic Concepts of Chemistry

Matter: Anything that has mass and occupies space.
- States: Solid, Liquid, Gas, Plasma.
Atoms: Basic units of matter.
- Composed of protons, neutrons, and electrons.
- Atomic number = number of protons.
- Mass number = protons + neutrons.
Elements: Pure substances made of only one type of atom.
- Listed in the periodic table.
- Examples: Hydrogen (H), Oxygen (O), Carbon (C).
Compounds: Substances formed from two or more different elements chemically bonded.
- Example: Water (H₂O), Carbon Dioxide (CO₂).

Ionic Bonds: Formed through the transfer of electrons from one atom to another.
- Typically between metals and nonmetals.
Covalent Bonds: Formed through the sharing of electrons between atoms.
- Typically between nonmetals.
Metallic Bonds: Involves the sharing of free electrons among a lattice of metal atoms.

Reactants: Substances that undergo a chemical change.
Products: Substances formed as a result of a chemical reaction.
Types of Reactions:
- Synthesis: A + B → AB
- Decomposition: AB → A + B
- Single Replacement: A + BC → AC + B
- Double Replacement: AB + CD → AD + CB
- Combustion: Hydrocarbon + O₂ → CO₂ + H₂O

Mole Concept: A mole represents 6.022 x 10²³ particles.
Molar Mass: The mass of one mole of a substance, usually expressed in g/mol.
Conversions:
- From grams to moles: grams/molar mass.
- From moles to molecules: moles x Avogadro's number.

Acids: Substances that donate protons (H⁺) in a solution.
- Example: Hydrochloric acid (HCl).
Bases: Substances that accept protons or donate hydroxide ions (OH⁻).
- Example: Sodium hydroxide (NaOH).
pH Scale: Measures the acidity or basicity of a solution.
- Scale ranges from 0 (acidic) to 14 (basic), with 7 being neutral.

Groups: Vertical columns that categorize elements with similar properties.
Periods: Horizontal rows showing elements with increasing atomic numbers.
Trends:
- Atomic radius decreases across a period and increases down a group.
- Electronegativity increases across a period and decreases down a group.

Hydrocarbons: Compounds consisting entirely of hydrogen and carbon.
- Types: Alkanes (single bonds), Alkenes (double bonds), Alkynes (triple bonds).
Functional Groups: Specific groups of atoms that determine the characteristics of organic compounds.
- Examples: Alcohols (-OH), Carboxylic acids (-COOH), Amines (-NH₂).

Personal Protective Equipment (PPE): Gloves, goggles, lab coats.
Safety Protocols: Proper handling and disposal of chemicals, understanding Material Safety Data Sheets (MSDS).

Matter: Defined as anything with mass that occupies space, existing in four states: solid, liquid, gas, and plasma.
Atoms: The fundamental building blocks of matter, composed of protons, neutrons, and electrons; the atomic number indicates the number of protons, while the mass number is the sum of protons and neutrons.
Elements: Pure substances consisting of only one type of atom, organized in the periodic table. Notable examples include Hydrogen (H), Oxygen (O), and Carbon (C).
Compounds: Formed by two or more different elements chemically bonded together. Examples include Water (H₂O) and Carbon Dioxide (CO₂).

Ionic Bonds: Created by the transfer of electrons, typically between metals and nonmetals, resulting in charged ions.
Covalent Bonds: Involve the sharing of electrons between nonmetals, leading to the formation of molecules.
Metallic Bonds: Characterized by a sea of shared free electrons among a lattice of metal atoms, giving rise to properties like conductivity.

Reactants: The initial substances that undergo transformation in a chemical reaction.
Products: The resulting substances formed after a chemical change has occurred.
Types of Reactions include:
- Synthesis: Combining elements or compounds (A + B → AB)
- Decomposition: Breaking down compounds into simpler substances (AB → A + B)
- Single Replacement: One element replaces another in a compound (A + BC → AC + B)
- Double Replacement: Exchange of ions between two compounds (AB + CD → AD + CB)
- Combustion: A hydrocarbon reacts with oxygen, producing carbon dioxide and water (Hydrocarbon + O₂ → CO₂ + H₂O).

Mole Concept: A mole represents 6.022 x 10²³ particles, serving as a bridge between the atomic scale and macroscopic quantities.
Molar Mass: The mass of one mole of a substance, typically expressed in grams per mole (g/mol).
Conversions:
- To convert grams to moles, divide by the molar mass.
- To convert moles to molecules, multiply by Avogadro's number.

Acids: Compounds that donate protons (H⁺) in a solution; a common example is Hydrochloric Acid (HCl).
Bases: Compounds that accept protons or donate hydroxide ions (OH⁻), such as Sodium Hydroxide (NaOH).
pH Scale: A logarithmic scale measuring the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic), with 7 indicating neutrality.

Exothermic Reactions: Reactions that release heat energy to the surroundings, causing temperature increase.
Endothermic Reactions: Reactions that absorb heat energy from the surroundings, leading to a temperature drop.
Enthalpy (ΔH): The heat content of a system at constant pressure, crucial in evaluating energy changes during reactions.

Groups: Vertical columns of the periodic table categorize elements with similar chemical and physical properties.
Periods: Horizontal rows indicate elements with increasing atomic numbers and differing properties.
Trends:
- Atomic radius decreases across a period while increasing down a group.
- Electronegativity increases across a period and decreases down a group.

Hydrocarbons: Organic compounds composed entirely of hydrogen and carbon, with subtypes classified as Alkanes (single bonds), Alkenes (double bonds), and Alkynes (triple bonds).
Functional Groups: Specific clusters of atoms within organic compounds that determine their chemical reactivity and characteristics. Examples include Alcohols (-OH), Carboxylic Acids (-COOH), and Amines (-NH₂).

Focuses on the study of inorganic compounds, including metals, minerals, and compounds that do not contain carbon-hydrogen bonds.

Personal Protective Equipment (PPE): Essential gear includes gloves, goggles, and lab coats to ensure safety during experiments.
Safety Protocols: Important procedures involve the proper handling and disposal of chemicals, as well as understanding Material Safety Data Sheets (MSDS) for hazard information.