Periodic Trends

Ionization energy is the...

• energy needed to remove the outermost electron.
• ability of an atom to attract electrons from another atom.

Electronegativity is the...

• energy needed to remove the outermost electron.
• ability of an atom to attract electrons from another atom.

Which element has the smaller atomic radius: potassium (K) or bromine (Br)?

• potassium (K)
• bromine (Br)

Which element has the greatest ionization energy: Aluminum (Al)    or    Chlorine (Cl)?

• Aluminum (Al)
• Chlorine (Cl)

Which element has the greatest electronegativity: Nitrogen (N) or Arsenic (As)?

• Nitrogen (N)
• Arsenic (As)

As you move down a group, atomic radius increases because - 

• you add more and more neutrons
• you add more and more protons
• you add more and more shells (energy levels)
• you add more atomic mass

The atom with the largest atomic radius in Group 18 is - 

• Ar
• He
• Kr
• Rn

As you move across the periodic table from left to right, the atomic radius decreases.  This is because - 

• the number of protons increases, so attraction to electrons increases
• the number of energy levels increases
• the number of electrons increases
• the atomic mass increases

The atom with the largest atomic radius in Period 4 (row 4) is - 

• K
• Kr
• Fe
• Fe

Francium (Fr) has the lowest ionization energy in Group 1 because - 

• it has the smallest number of valence electrons
• it has the greatest atomic mass
• it has the greatest number of protons, so it attracts its electrons the strongest
• its 1 valence electron is very far from the nucleus, so little energy is needed to remove it