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)

Which element in Period 2 has the greatest atomic radius?

• Be

• C

• Na

• Li

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

Electronegativity __________ from left to right within a period and __________ from top to bottom within a group.

• decreases, increases 
• increases, increases
• increases, decreases 
• stays the same, increases

Which of the following will have a lower ionization energy than Scandium (Sc)?

• Helium (He)

• Titanium (Ti)

• Calcium (Ca)

• Magnesium (Mg)

In the modern periodic table elements are arranged by:

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