Periodic Trends 3

Periodic Trends: 

Periodic Trends By: Katie Green, T’mya Cunningham and Samantha Farley

Atomic Radius: 

Atomic Radius The distance from the atom to the outer electrons.

Slide3: 

The atomic radius decreases as you move from left to right across the periodic table. The attractive force between the negatively charged electrons and the positively charged protons in the nucleus.

Ionization Energy: 

Ionization Energy The energy required to remove an electron from an atom/atoms.

Slide6: 

The ionization energy decreases as you move from top to bottom on the periodic table. By quantum mechanics the number of electron shells increases making the atomic radius larger.

Ionization Energy: 

Ionization Energy As you move from left to right across the periodic table, the ionization energy gets bigger. Why? It requires more energy to get rid of the outer electrons where there are more valence electrons.

Ionization Energy: 

Ionization Energy

Electronegativity: 

Electronegativity A chemical property that describes the power of an atom to attract electrons to itself.

Slide10: 

Electronegativity is helpful in finding if a bond is nonpolar covalent, polar covalent, or ionic. How do you find electronegativity? From the electronegativity chart:

Electronegativity cont’d: 

Electronegativity cont’d As you move from left to right across the periodic table, the electronegativity gets bigger. It increases because the atomic radius gets smaller, therefore electrons can get really close to the nucleus because of the strong attractive force. As you move from top to bottom on the periodic table the electronegativity gets smaller. Decreases because the atomic radius increases so the attractive force between the protons and electrons isn’t as strong.

What kind of bond is it?: 

What kind of bond is it? Nonpolar covalent, polar covalent, or ionic? Find the electronegativities of each atom and subtract the lower from the higher. Next use the chart below to determine what type of bond.