Periodic Table and Bonding Concepts

These flashcards cover key vocabulary and concepts from the lecture on the periodic table, bonding, and chemical reactions.

Periodic Table

A list of all known elements arranged by increasing atomic number and grouped by similar electronic configurations.

Atomic Number

The number of protons in the nucleus of an atom, determining the element's position in the periodic table.

Period

A row in the periodic table; elements in the same period have the same number of electron shells.

Group

A column in the periodic table; elements in the same group have similar chemical properties and electronic configurations.

Valence Electrons

Electrons in the outer shell of an atom that determine its chemical properties.

Periodic Trends

Patterns in the properties of elements as you move across a period or down a group in the periodic table.

Ionisation Energy

The energy required to remove an electron from an atom in the gaseous state.

Nuclear Charge

The total charge of the nucleus, determined by the number of protons.

Electron Shielding

The phenomenon where inner shell electrons reduce the effective nuclear charge felt by outer shell electrons.

Giant Covalent Lattice

A three-dimensional structure formed by atoms connected by covalent bonds, resulting in strong bonding.

Metallic Bonding

The bonding that occurs between metal atoms, characterized by a 'sea' of delocalised electrons.

Covalent Bond

A bond formed when two nonmetal atoms share a pair of electrons.

Exothermic Reaction

A reaction that releases energy in the form of heat, resulting in an overall decrease in enthalpy.

Endothermic Reaction

A reaction that absorbs energy, resulting in an overall increase in enthalpy.

Catalyst

A substance that increases the rate of a chemical reaction by lowering the activation energy.

Dynamic Equilibrium

The state in which the rate of the forward reaction equals the rate of the reverse reaction, and concentrations of reactants and products remain constant.

Le Chatelier's Principle

The principle stating that if a system at equilibrium is disturbed, the system shifts in a direction that counteracts the disturbance.

Electronegativity

The ability of an atom to attract electrons in a bond; higher values indicate a stronger pull.

Hydrogen Bonding

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

Standard Enthalpy Change

The heat change associated with a chemical reaction occurring at standard conditions (298 K and 100 kPa).