Atoms and Elements

What are the four most common elements found in living things?

• Carbon, Iron, Hydrogen and Oxygen
• Carbon, Hydrogen, Oxygen, Nitrogen
• Sulfur, Potassium, Calcium, Iron
• Oxygen, Carbon, Nitrogen, Helium 

The positive particles of an atom are 

• electrons 
• positrons 
• neutrons 
• protons 

All matter is made of what?

• energy 
• atoms 
• electrons 
• compounds 

The central region of an atom where its neutrons and protons are is its 

• nucleus 
• electron cloud
• core 
• center 

An atom with atomic number 6 would have how many protons 

• 6
• 12
• 3
• cannot be determined 

Particles in an atom that are neutral and have no charge are 

• negatrons 
• electrons 
• neutrons 
• protons 

True or False? Neutrons have a negative charge

• True
• False

What is the atomic number for an element with three protons?

• 2
• 1
• 3
• 6

A particle that moves around the nucleus is a(n)...

• Proton
• Neutron
• Electron
• Quark

The atomic mass is equal to 

• the atomic number
• the number of protons
• the number of protons and neutrons
• the number of electrons