Vocabulary chapter 1 atomic structure and the periodic table

Periodic table

A table showing a repeating pattern of properties of the elements

Neutron

An atomic particle that has no charge

Proton

An atomic particle that is postively charged

Isotope

An element that has the same number of protons but different number of neutrons in the nucleus

Period

Each horizontal row in the periodic table

Metals

Elements that conduct electricity and heat well, and have a shiny appearance

Metalloid

Elements that have properties of both metals and nonmetals

Ion

Formed when an atom loses or gains one or more electrons

Atomic mass

It's the average mass of the isotopes of atoms of an element

reactive

Term used indicates how likely the element is to undergo a chemicals change

Half life

The amount of time it takes for one half of the atoms in a particular sample to decay

Electrons

The atomic particle that is negatively charged and moves around the outside of the nucleus

Group

The elements In a column in the periodic table

Nonmetals

The elements on the right side of the periodic table that have properties opposite of those metals

Atomic number

The number of protons in an atoms nucleus, which serves to identify an atom

Nucleus

The part of an atom that contains protons and neutrons

Radioactive

The process by which atoms produce energy and produce particles

Atomic mass number

The sum of an atoms protons and neutrons