Unit 3 Review (2023)

A(n) ____ is the smallest particle of an element that retains the element’s properties.

• isotope
• atom
• electron cloud

The small, positively charged center of the atom which contains protons & neutrons is the ___.

• nucleus
• proton
• electron cloud

The number of ____ identifies an element and is unique for each element

• electrons
• neutrons
• protons

The neutral particle of the atom are the

• electrons
• neutrons
• protons

The __ have an electrical charge of 1-.

• electrons
• neutrons
• protons

A(n) __ is a smaller particle of matter that makes up protons and neutrons.

• electron
• isotope
• quark

The __ is the area around the nucleus where electrons are most likely to be found.

• electron cloud
• nucleus
• mass number

The __ is always the same as the number of protons.

• atomic mass
• atomic number
• valence electron

The __ is the sum of the number of protons and neutrons in the nucleus of an atom.

• atomic mass
• atomic number
• valence electron

__ are atoms of the same element that have different numbers of neutrons.

• quarks
• isotopes
• electron cloud