A substance that cannot be broken down any further without losing its properties.

• Compound

• Mixture

• Element

• Suspension

Subatomic particle with a positive charge

• Proton

• Neutron

• Electron

Subatomic particle with a negative charge

• Proton

• Neutron

• Electron

Subatomic particle(s) located in the shells outside the nucleus

• Proton

• Neutron

• Electron

Atoms are mostly...

• Tightly packed

• Empty space

The mass of an atom is found by adding which subatomic particles?

• Protons

• Neutrons

• Electrons

The number of _______________ in an atom is represented by its atomic number.

• Protons

• Neutrons

• Electrons

How many protons does Helium (He) have?

• 1

• 2

• 3

• 4

What is the element symbol for boron? 

• B
• Bo
• Bn
• W

All Elements are either _________________, _____________________, ____________________. (select all that apply)

• Metals

• Non-metals

• liquids

• metalloids

• rocks