Atoms and Elements

This set of flashcards covers key vocabulary related to atoms, elements, and their properties, as discussed in the provided lecture notes.

Matter

Anything that takes up space and has mass.

Element

A substance that cannot be broken down into other substances by chemical reactions.

Compound

A substance consisting of two or more elements in a fixed ratio, with emergent properties.

Emergent properties

Characteristics of a compound that are different from those of its elements.

Atomic number

The number of protons in an atom, unique for each element.

Mass number

The total number of protons and neutrons in the nucleus of an atom.

Isotope

Atoms with the same number of protons but different numbers of neutrons.

Atomic mass

The sum of protons and neutrons of a single atom.

Atomic weight

The weighted average of the atomic mass of all natural isotopes of an element.

Nucleus

The inner part of an atom made up of protons and neutrons.

Electron

A particle found orbiting around the nucleus of an atom, carrying a negative charge.

Proton

A positively charged particle found in the nucleus of an atom.

Neutron

A neutral particle found in the nucleus of an atom.

Trace elements

Elements required by the body in very small amounts, less than 0.01% of body mass.

Valence electrons

Electrons in the outermost shell of an atom that determine its chemical reactivity.