Unit 6 Test Review

Atoms of elements in the same group of the periodic table share the same

• number of energy levels

• number of valence electrons

• atomic numbers

• atomic masses

What is an atom’s nucleus made of?

• Protons and electrons

• Protons only

• Protons and neutrons

• Neutrons only

The farther an electron is from the nucleus, the more ______ it has.

• charge

• energy

• mass

• size

Atoms of the same element that have different numbers of neutrons are called

• molecules

• ions

• protons

• isotopes

 The total number of electrons in the outer shell of a sodium atom is

• 1

• 2

• 8

• 18

Which particles determine the atomic number of an element?

• Protons only

• Neutrons and protons

• Neutrons only

• Protons and electrons

The total number of neutrons in the nucleus of an atom is equal to the

• mass number of the atom

• atomic number of the atom

• atomic number minus the mass number

• mass number minus the atomic number

The maximum number of electrons that can occupy the 2nd shell of an atom of magnesium is 

• 1

• 2

• 8

• 18

The mass of the most common isotope of an element is known based on an element’s

• Mass number

• Average atomic mass

• Atomic number

• Number of electrons

What is the correct electron arrangement for sulfur? (Hint: think about electron shells/energy levels!) 

• 2-8-6

• 2-8-8

• 4-6-2

• 2-8-4