mid 1 lec1-4 not mine.1

not my notes.1

Hydrogen

Element with atomic number 1 and symbol H, classified as a non-metal.

Atomic Theory of Matter

Theory that states all matter is composed of atoms, which are the smallest indivisible particles.

Isotopes

Atoms of the same element with different masses due to varying numbers of neutrons.

Periodic Table

A systematic organization of elements arranged by increasing atomic number.

Chemical Bonds

Forces that hold atoms together in molecules, including ionic and covalent bonds.

Cation

A positively charged ion that has lost one or more electrons.

Anion

A negatively charged ion that has gained one or more electrons.

Electronegativity

The tendency of an atom to attract electrons toward itself in a chemical bond.

Lone Pairs

Electrons that are located on only one atom and are not shared with other atoms in a bond.

Phase Change

A transition from one state of matter (solid, liquid, gas) to another, involving energy changes.

Solubility

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

Intermolecular Forces

Attractive forces between molecules, which determine physical properties like boiling and melting points.

Homogeneous Mixtures

Uniform mixtures with the same composition throughout.

Heterogeneous Mixtures

Non-uniform mixtures with different compositions in various parts.

Lewis Structures

Diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons.

Valence Electrons

Electrons found in the outermost shell of an atom that participate in chemical bonding.

Kinetic Energy

The energy of motion that keeps molecules apart and moving in different states of matter.

Molarity (M)

A measure of the concentration of a solution, defined as the number of moles of solute per liter of solution.

Density

Mass per unit volume of a substance, often used to distinguish between different phases.