Chemical Bonds: Formation, Types, and Properties
Chemical Bonds
Chemical bonds form between atoms to achieve greater stability, often attaining a noble gas electron configuration. Bonds can be homoatomic (same atom) or heteroatomic (different atoms).
Ionic Bonds
Ionic bonds form between metals and nonmetals. Nonmetals gain electrons to form anions, achieving the nearest noble gas configuration. Metals lose electrons, forming cations. Stoichiometry depends on anion and cation charges.
Covalent Bonds
Covalent bonds form between nonmetals. Atoms share
Read MoreStoichiometry, Solutions, Kinetics, and Chemical Equilibrium
Stoichiometry is the field of chemistry that studies the relationships between the quantities involved in a chemical reaction. The laws governing stoichiometry are:
- Law of definite proportions: when you combine two or more elements for a given compound, they always do so with a relationship of constant mass.
- Law of constant composition: All chemical elements in a pure state always contain the same elements.
- Law of conservation of mass: Matter is not created or destroyed, only transformed.
Stoichiometry
Read MoreChemical Bonding: Forces, Structures, and Properties
Chemical Bonds
A chemical bond is the union between atoms, molecules, or ions. Lewis explained that atoms lose or share electrons to achieve a noble gas electron configuration, with 8 electrons in the valence layer.
Forces in Bond Formation
When atoms approach to form a bond, forces appear due to the charges in the atom:
- Attractive forces: Occur between the nucleus of each atom and the electron cloud of the other.
- Repulsive forces: Exist between the nuclei and between the electron shells.
A bond forms
Read MoreAtomic Orbitals and Electron Configurations
1. Atomic Orbitals and Quantum Numbers
Quantum Mechanical Model of the Atom
The quantum mechanical model describes the atom based on fundamental quantum mechanics principles. A key consequence of the uncertainty principle is the impossibility of precisely defining an electron’s trajectory.
Atomic Orbitals and Quantum Numbers
Each atomic orbital is characterized by three quantum numbers and possesses a specific energy level derived from the Schrödinger equation. Placing electrons in these orbitals
Read MoreFundamental Chemistry Concepts: Laws, States, and Bonding
Fundamental Chemical Laws
Law of Conservation of Matter (Lavoisier)
Matter is neither created nor destroyed, only transformed. The mass of the reactants equals the mass of the products.
Law of Definite Proportions (Proust)
Whenever two or more elements combine to form a compound, they do so in a constant mass ratio.
Law of Multiple Proportions (Dalton)
When two elements combine to form more than one compound, the masses of one element that combine with a fixed mass of the other are in ratios of small
Read MoreChemical Reactions: Energy, Enthalpy, and Reaction Rates
Chemical Reactions and Energy
Compounds or chemicals release stored energy in several ways:
- Thermal Energy (leads to temperature changes)
- Mechanical Energy (movement of objects)
- Electrical Energy (electricity from chemical reactions, like in batteries)
- Light Energy
- Other forms of energy (e.g., sound waves)
Origin of Energy Exchange in Chemical Reactions
Any chemical reaction involves interactions between reacting species that cause bond breaking and formation. Remember:
- Bond Rupture: Requires energy input.