Negatively charged atomic particle outside the nucleus of an atom.

Tiny region in the center of an atom that contains protons and neutrons and makes up almost all of an atom’s mass.

Electrically neutral atomic particle inside the nucleus of an atom.

Column of the periodic table that contains elements with similar properties.

Atom of an element that differs in number of neutrons from other atoms of the element.

Particle of matter that makes up protons and neutrons.

Positively charged atomic particle inside the nucleus of an atom.

Positively or negatively charged form of an atom that has lost or gained electron(s).

Region of an energy level in the electron cloud around an atom where electrons are most likely to be.

________________ are the building blocks of all matter.

The nucleus consists of two types of particles, called _________________ and ____________________.

What is the SI unit for the mass of an atom? ______________________

Ions are atoms that gain or lose _________________.

Isotopes are named by their ________________number.

The history of the atom begins around 450 BC with a Greek philosopher named ___________________

Around 1800, a British chemist named ___________ revived the ideas about an atom.

After Dalton, the next major advance in the history of the atom was the discovery of ___________________, which was the work of __________________.

The development after Thompson was by a physicist named _________________________who discovered the ______________.

Danish physicist ______________________ created a model of the atom that was more accurate and useful than that of Rutherford.

The fixed distances electrons orbit around the nucleus are called ______________ _____________

Today, ideas about electrons are represented by the _____________ ___________ model.

The denser areas of electron clouds are the regions where electrons are most ____________ to be. These areas are called __________________.

How many electrons can there be in each orbital? ________

Mendeleev’s table is called a _______________ _____________ because of its repeating patterns.

In the modern periodic table, elements are organized by ___________ _____________.

Which of the following are the three classes of elements

__________ of the modern table are called periods.

How many groups are in the modern periodic table? ______

Elements in different groups are lumped together into one of three classes depending on their properties. These classes are _____________, ___________________, and __________________________.​

Metals are shiny, ductile, and malleable

Electrons are added first to the _________________ energy level possible until that level is ____________.

Where are the valence electrons located in an atom?

The number of valence electrons determines an elements reactivity and whether an element can _____________ ______________ _________.

Elements in the same column, or _______________, of the periodic table have the same number of ________________ ___________________ in their outer energy level.

What element is the most common element in the universe? ___________________

The elements in group 2 are known as the ________________ ___________ ______________.

Groups 3-12 of the periodic table contain __________________ metals.

Group 18 elements are nonmetals called ____________ gases. They are _________________, ________________ gases. Their outer energy level is also full, so they are the ______________ reactive.