Chemistry: Exploring the Fundamental Concepts and Topics

Atomic Structure

The composition of atoms with protons, neutrons, and electrons,

Protons

Positively charged particles found in the nucleus of an atom. Each proton has a relative charge of +1 and a relative mass of 1 atomic mass unit (amu).

Neutrons

Neutral particles also located in the nucleus. They have no charge and a relative mass similar to that of protons, approximately 1 amu.

Electrons

Negatively charged particles that orbit the nucleus in electron shells. Each electron has a relative charge of -1 and a much smaller mass compared to protons and neutrons, approximately 1/1836 of an amu.

Atomic Number (Z)

The number of protons in the nucleus of an atom, which determines the element's identity and its position in the periodic table.

Mass Number (A)

The total number of protons and neutrons in an atom's nucleus. It can be calculated as:

• Mass Number = Number of Protons + Number of Neutrons

Periodic Table

A tabular arrangement of elements based on atomic number and properties, with periods indicating electron shells and groups sharing similar properties.

Periods (Rows):

Horizontal rows in the periodic table. The period number indicates the number of electron shells in the atoms of the elements in that period.

Groups (Columns)

Vertical columns in the periodic table. Elements in the same group have the same number of valence electrons, resulting in similar chemical properties.

Ionization Energy

The energy required to remove an electron from an atom. It generally increases across a period and decreases down a group.

Electronegativity

A measure of an atom's ability to attract and bond with electrons. It increases across a period and decreases down a group.

Chemical Bonding

Includes ionic bonding (electron transfer), covalent bonding (electron sharing), and metallic bonding (delocalized electrons in metals).

Chemical Reactions

Involving synthesis, decomposition, single and double replacement, combustion, studied through stoichiometry and reaction rates.

Synthesis (Combination) Reaction

what type of chemical reactions?

• Two or more simple substances combine to form a more complex substance. A + B → AB

Decomposition Reaction

what type of chemical reactions?

• A complex substance breaks down into two or more simpler substances. AB → A + B

Single Replacement Reaction

what type of chemical reactions?

• One element replaces another in a compound. A + BC → AC + B

Double Replacement Reaction

what type of chemical reactions?

• The ions of two compounds exchange places to form two new compounds. AB + CD → AD + CB

Combustion Reaction

what type of chemical reactions?

• A substance reacts with oxygen, releasing energy in the form of light and heat. Typically involves hydrocarbons. CₓHy + O2 → CO₂ + H₂OC

balanced equation

Principles of Stoichiometry:

• Based on the conservation of mass and the mole concept. Uses molar ratios derived from the __________ to calculate the amounts of reactants and products.

States of Matter

Solid (definite shape/volume), liquid (definite volume, no shape), gas (no definite shape/volume, highly compressible).

Solid

What state of matter?

• Ice, where water molecules are arranged in a crystalline structure.

Liquid

What state of matter?

• Water, which can flow and take the shape of its container.

Gas

What state of matter?

• Oxygen, which fills the entire volume of its container.

Acids

Substances that release hydrogen ions (H⁺) in aqueous solution, turning litmus paper red and reacting with metals to produce hydrogen gas.

Acids

Properties: Sour taste, turn blue litmus paper red, react with metals to produce hydrogen gas.

Hydrochloric acid (HCl), which dissociates in water to produce H⁺ and Cl⁻ ions.

Example of an acid?

Bases

Substances that release hydroxide ions (OH⁻) in aqueous solution, turning litmus paper blue and feeling slippery to the touch.

Bases

Properties: Bitter taste, slippery feel, turn red litmus paper blue.

Sodium hydroxide (NaOH), which dissociates in water to produce Na⁺ and OH⁻ ions.

Example of a base

Organic Chemistry

Focuses on carbon compounds, functional groups (determining properties), and isomerism (same formula, different properties).

Reaction Kinetics and Equilibrium

Reaction rates influenced by factors like temperature, concentration, catalysts; equilibrium is a balance between forward and reverse reactions, Le Chatelier's Principle predicts equilibrium shifts.

three

Atoms are composed of ____ main subatomic particles: protons, neutrons, and electrons.

isotopes

Atoms of the same element with different numbers of neutrons are called _____, they may have different atomic masses but the same atomic number.

ionic bonding

A type of chemical bond formed through the electrostatic attraction between oppositely charged ions. Formed by the transfer of electrons from one atom to another, resulting in the formation of ions with opposite charges that attract each other.

Ionic Bonding

what type of chemical bonding?

• Sodium chloride (NaCl), where sodium (Na) donates an electron to chlorine (Cl), forming Na⁺ and Cl⁻ ions.

covalent bonding

A type of chemical bond where two atoms share one or more pairs of valence electrons. Formed by the sharing of electrons between atoms, resulting in the formation of molecules with stable electron configurations.

Covalent Bonding

what type of chemical bonding?

• Water (H₂O), where each hydrogen atom shares electrons with the oxygen atom.

metallic bonding

Found in metals, where delocalized electrons move freely between positively charged metal ions, creating a "sea of electrons" that holds the metal atoms together.

Metallic Bonding

what type of chemical bonding?

• Copper (Cu), where the delocalized electrons allow it to conduct electricity and heat.

Stoichiometry

The quantitative study of reactants and products in chemical reactions based on the principles of conservation of mass and the mole concept.

temperature, concentration, surface area, and the presence of catalysts.

Factors affecting the rate of chemical reactions, including:

solid

Particles are closely packed in a regular arrangement, with strong forces of attraction between them. Solids have definite shape and volume.

liquid

Particles are close together but can move past each other, allowing liquids to flow and take the shape of their containers. Liquids have definite volume but no definite shape.

gas

Particles are far apart and move freely, filling the entire volume of their container. Gasses have neither definite shape nor volume and are highly compressible.

acids

Substances that release hydrogen ions (H⁺) in aqueous solution, turning litmus paper red and reacting with metals to produce hydrogen gas.

bases

Substances that release hydroxide ions (OH⁻) in aqueous solution, turning litmus paper blue and feeling slippery to the touch.

Neutralization Reactions

Reactions between acids and bases to form water and a salt, accompanied by the transfer of protons.

Carbon Compounds

focuses on the study of carbon-containing compounds, including hydrocarbons, alcohols, carboxylic acids, and carbohydrates.

Carbon Compounds

Examples: Hydrocarbons (methane, ethane), alcohols (ethanol), carboxylic acids (acetic acid), carbohydrates (glucose).

functional groups

Groups of atoms within organic molecules that determine their chemical properties and reactivity, such as hydroxyl (-OH), carbonyl (>C=O), and amino (-NH2) groups.

Functional Groups

Hydroxyl group (-OH) in alcohols, carbonyl group (>C=O) in ketones and aldehydes, amino group (-NH₂) in amines.

isomerism

The phenomenon where organic compounds with the same molecular formula but different structural arrangements exhibit different properties.

Structural isomers

type of isomerism that differ in the arrangement of atoms

stereoisomers

type of isomerism that differ in the spatial arrangement of atoms

reaction rates

The speed at which chemical reactions occur, influenced by factors such as temperature, concentration, and the presence of catalysts.

1. Temperature

2. concentration

3. surface area

4. catalysts

Factors Influencing Reaction Rates:

1. _______ (increases kinetic energy)

2. _______ (increases collision frequency)

3. _______ (increases contact area)

4. ________ (lowers activation energy).

chemical equilibrium

Dynamic balance between forward and reverse reactions in a reversible chemical reaction, characterized by constant concentrations of reactants and products.

constant

Chemical Equilibrium Characteristics: At equilibrium, the system is dynamic, meaning reactions continue to occur but the overall concentrations remain ______.

Le Chatelier's Principle

Predicts how changes in temperature, pressure, or concentration affect the position of equilibrium in chemical reactions.

Le Chatelier's Principle

Example: Increasing the concentration of reactants will shift the equilibrium towards the products.

Heat

A form of energy transfer between bodies due to a temperature difference.

Temperature

A measure of the average kinetic energy of particles in a substance.

Enthalpy (ΔH)

The heat content of a system at constant pressure.

Exothermic Reactions

Reactions that release heat to the surroundings.

Endothermic Reactions

Reactions that absorb heat from the surroundings.

Calorimetry

The measurement of heat changes in physical and chemical processes.

Calorimeter

An instrument used to measure the amount of heat involved in a chemical or physical process

Redox Reactions

Reactions involving the transfer of electrons.

Oxidation

Loss of electrons reaction.

Reduction

Gain of electrons reaction.

Oxidizing Agent

The substance that gains electrons.

Reducing Agent

The substance that loses electrons

Galvanic (Voltaic) Cell

Converts chemical energy into electrical energy through spontaneous redox reactions.

Electrolytic Cell

Uses electrical energy to drive non-spontaneous redox reactions.

Radioactivity

The spontaneous emission of particles or radiation from unstable atomic nuclei.

Nuclear Fission

The splitting of a heavy nucleus into lighter nuclei, accompanied by the release of energy.

Nuclear Fusion

The combining of light nuclei to form a heavier nucleus, accompanied by the release of energy.

Half-life (t₁/₂)

The time required for half of the radioactive nuclei in a sample to decay.

Solutions

Homogeneous mixtures of two or more substances.

Solvent

The substance in greater amount in a solution.

Solute

The substance in lesser amount in a solution.

Solubility

The maximum amount of solute that can dissolve in a given amount of solvent at a specific temperature.

The amount of solute present in a given quantity of solvent or solution.

Concentration

Molarity (M)

Moles of solute per liter of solution.

Kinetic Molecular Theory

A theory that describes the behavior of gases, assuming they consist of small particles in constant, random motion.

Air Pollution

The contamination of air by harmful substances.

Water Pollution

The contamination of water bodies by pollutants.

Green Chemistry

The design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances.

Greenhouse Gases

Gases like carbon dioxide, methane, and nitrous oxide that trap heat in the atmosphere.

Climate Change

The effects of increased greenhouse gases, such as global warming and changes in weather patterns.

Hybridization

The mixing of atomic orbitals to form new hybrid orbitals that can form sigma bonds.

Molecular Orbital Theory

A theory that describes the distribution of electrons in molecules in terms of molecular orbitals that can extend over several atoms.

VSEPR Theory

A theory predicting the shape of molecules based on the repulsion between electron pairs around the central atom.

Transition Metals

Elements in groups 3-12 of the periodic table with partially filled d orbitals are called?

Coordination Compounds

Compounds consisting of a central metal atom or ion bonded to surrounding ligands are called?

Ligands

Molecules or ions that donate a pair of electrons to the metal in a coordination compound

Spectroscopy

Crystal Field Theory

Polymers

Large molecules made up of repeating units called monomers.

Thermoplastics

Polymers that soften upon heating and can be reshaped.

Condensation Polymers

Polymers formed by the combination of monomers with the loss of a small molecule such as water.