Periodic table

Who invented the Periodic Table?

• Mendeleev

• Bohr

• Lewis

• Democritus

Mendeleev's genius was his ability to

• predict elements that were not discovered yet

• organize elements by their mass

• had an element named after himself

• organize elements by properties

The atomic number tells you what?

• number of electrons
• number of protons
• number of neutrons
• both electrons and protons in an atom.

The positive particles of an atom are 

• electrons 
• positrons 
• neutrons 
• protons 

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

• negatrons 
• electrons 
• neutrons 
• protons 

The subatomic particle with a negative charge is the

• electron
• proton
• neutron
• nucleus 

In the modern periodic table elements are arranged by:

• atomic mass
• atomic number
• valence electrons
• number of isotopes

How many protons are in a nitrogen atom?

• 5

• 7

• 14

• 28

How many protons are in a nitrogen atom?

• 5

• 7

• 14

• 28

What is the chemical symbol for sodium?

• S

• So

• Na

• K