Chem Chapter 2,3,4

Independent variable

The variable that is changed or controlled in a scientific experiment to test its effects on the dependent variable.

Dependent variable

The variable that is being measured and affected in an experiment.

Controlled variables

All the variables that are kept constant or unchanged to ensure that the experiment tests only the independent variable.

VSEPR theory

A model used to predict the geometry of individual molecules based on the repulsion between the pairs of electrons around a central atom.

Covalent bond

A type of chemical bond where two atoms share one or more pairs of electrons.

Intramolecular forces

Forces that occur within a molecule, affecting its structure.

Intermolecular forces

Forces that occur between molecules, affecting properties such as boiling and melting points.

Dispersion forces

Weak intermolecular forces resulting from the temporary shifts in electron density in nonpolar molecules.

Dipole-dipole attractions

Attractions between positively charged ends of one polar molecule and negatively charged ends of another polar molecule.

Hydrogen bonding

A strong type of dipole-dipole attraction that occurs between molecules when a hydrogen atom is bonded to a highly electronegative atom.

Polar molecules

Molecules that have a net dipole moment due to the presence of polar bonds.

Non-polar molecules

Molecules that do not have regions of positive or negative charge, resulting in a balanced distribution of electrical charge.

Metallic bonding model

A model describing a metal's structure where positively charged metal ions are surrounded by a sea of delocalized electrons.

Malleability

The property of a material that allows it to be deformed under compressive stress, often characterized by the ability to form thin sheets.

Ductility

The ability of a material to be stretched into a wire without breaking.

Ionic bond

A type of chemical bond formed through the electrical attraction between oppositely charged ions.

Ionic compounds

Compounds formed from ionic bonds, typically consisting of metal cations and non-metal anions.

Electrostatic forces

Forces of attraction or repulsion between charged particles.

Solubility

The ability of a substance to dissolve in a solvent.

Precipitate

A solid that forms and separates from a liquid mixture during a chemical reaction.

Balanced equation

An equation in which the number of atoms for each element is the same on both sides of the reaction.

Ionic equation

A chemical equation that shows only the particles that participate in the reaction, excluding spectator ions.

Spectator ions

Ions that do not participate in the actual chemical reaction and remain in the solution.