Principles of Chemistry: Ions, Bonds, and Stoichiometry

Ions

Atoms with net electric charge due to electron loss/gain.

Cations

Positively charged ions formed by electron loss.

Anions

Negatively charged ions formed by electron gain.

Ionic Bonding

Attraction between oppositely charged ions.

Ionic Radius

Radius of an ion's electron cloud.

Radius Ratio Rule

Predicts ionic structure based on cation/anion size.

Electronegativity

Atom's ability to attract bonding electrons.

Covalent Bonding

Sharing of valence electrons between atoms.

Bond Length

Distance between nuclei at minimum energy.

Bond Energy

Energy needed to separate bonded atoms.

Atomic Orbitals

Regions where electrons are likely found.

Isoelectronic Series

Atoms/ions with same electron configuration.

Molecular Shape

Geometric arrangement of atoms in a molecule.

Valence Bond Theory

Explains covalent bonding through overlapping orbitals.

Radial Nodes

Regions in orbitals where probability of finding electrons is zero.

Angular Nodes

Regions in orbitals where electron probability is zero due to angular momentum.

Chemical Reactions

Processes where substances transform into different substances.

Bond Pair

Two electrons shared between two atoms in a covalent bond.

Octahedral Geometry

Ionic structure with 6:6 coordination of ions.

Cubic Geometry

Ionic structure with 8:8 coordination of ions.

Tetrahedral Geometry

Ionic structure with 4:4 coordination of ions.

Lone Pair (lp)

Valence electron pair not involved in bonding.

Unpaired Electron (upe)

Electron that is alone in an orbital.

Octet Rule

Atoms form stable compounds with 8 valence electrons.

Bond Polarity

Distribution of electron density in a bond.

Homonuclear Bonds

Bonds between identical atoms, non-polar.

Heteronuclear Bonds

Bonds between different atoms, may be polar.

Dipole Moment (µ)

Measure of bond polarity, in Debye units.

Molar Mass (Mr)

Mass of 1 mole of a substance in grams.

Molecular Formula

Actual number of atoms in a molecule.

Limiting Reagent

Reactant that is completely consumed first.

Theoretical Yield

Maximum amount of product from a reaction.

Gravimetric Analysis

Determines concentration by weighing a product.

Covalent Non-Polar Bond

Bond with equal sharing of electrons.

Covalent Polar Bond

Bond with unequal sharing of electrons.

Hill Notation

C first, H second, others in alphabetical order.

Molecular Weight (MW)

Sum of atomic weights in a molecular formula.