Atomic Structure - Atoms

Vocabulary flashcards covering core concepts of atomic structure, elements, compounds, and the periodic table from Topic 1.1.

Atom

The smallest part of an element that can exist; tiny particles that make up all substances and consist of a central nucleus surrounded by orbiting electrons.

Element

A substance that is made up of only one type of atom, with about $100$ different types found naturally on Earth.

Compound

A substance made up of different types of atoms chemically bonded tightly together.

Chemical symbols

Internationally understood letter representations for atoms of elements shown in the periodic table, such as $\text{O}$ for oxygen and $\text{Na}$ for sodium.

Periodic table

A table showing the symbols for each type of atom, arranged in columns with eight main groups containing elements with similar chemical properties.

Groups

The vertical columns in the periodic table, each containing elements with similar chemical properties.

Metalloids (semi-metals)

Elements lying next to the staircase dividing line on the periodic table that possess some metallic and some non-metallic properties, such as silicon ($\text{Si}$) and germanium ($\text{Ge}$).

Molecule

A grouping of two or more atoms bonded together, such as in water ($\text{H}_2\text{O}$).

Chemical bonds

Forces that hold atoms tightly together in compounds.

Nucleus

The tiny central part at the centre of an atom, surrounded by orbiting electrons.

Electrons

Particles that orbit around the tiny central nucleus of an atom.