Chapter 1 Study Guide

The smallest piece of an element that still represents the element.

• Atom

• Neutron

• Proton

• Nucleus

A particle with one negative charge

• Atom

• Neutron

• Proton

• Electron

A small area in the center of the atom where most of an atom's mass and positive charge is concentrated

• Neutron

• Proton

• Nucleus

• Electron

An atomic particle that has one positive charge

• Atom

• Proton

• Nucleus

• Electron

A neutral particle that exists in the nucleus of an atom

• Atom

• Neutron

• Nucleus

• Electron

An area around an atomic nucleus where an electron is most likely to be located

• Electron cloud

• Mass number

• Isotope

• Atomic Number

The number of protons in an atom of an element

• Electron cloud

• Mass number

• Isotope

• Atomic Number

Atoms of the same element that have different numbers of neutrons

• Electron cloud

• Mass number

• Isotope

• Atomic Number

The sum of the number of protons and neutrons in an atom

• Electron cloud

• Mass number

• Isotope

• Atomic Number

The average mass of the element's isotopes, weighted according to the abundance of each isotope

• Ion

• Nuclear decay

• Radioactivity

• Average atomic mass