Chem unit 5 part 2

As you go across a period

• The zeff increases

• Elecronegativity increases

• The zeff is higher the overall attractive force an atom has on its valence electrons increases

• The ability to attract electrons will increase

As you go across a period

• Zeff increases

• Ionization energy increases

• The higher the zeff the more difficult it is to remove an electron from an atoms

• Ionization energy required increases

Down a group

• Zeff decreases

• Atomic radius increases

• The lower the zeff the lower the less the valence electrons are attracted inward to the nucleus

• The core electrons are gettin bigger and the valence electrons are in a higher principle level

As you go down a group z

• The zeff decrease

• ionization energy increases

• The lower the zeff the less the electron is being help by the nucleus

• Removing the electron will require less energy

The size, electroneagtivity and ionization energy are all determined by the overall

• attractive force

• molecular weight
• nuclear charge
• electron affinity

More zeff felt on valence electrons

• atom would be smaller

• High ability to attract electrons

• require a larger energy to have one valence electron removed from it

• Less Zeff is felt on valence electrons as you move across a period.

Less overall attractive force felt on electrons

• Atom would be bigger

• A low ability to attract electrons

• Require a smaller energy to have one valence electron removed from it

• High ability to attract electron

Zeff _____ across a period and ______ down a group

• decreases; increases
• remains constant; increases
• increases; increases
• increases; decreases

Why are there a few exceptions in the D and F sublevels

• energies of the sublevels are so close and the electron behavior gets influence by other electrons

• Exceptions are due to the presence of unpaired electrons only.
• D and F sublevels are always filled before other sublevels.
• The exceptions are random and have no specific reason.

All chemical preprocess are influenced by the common number of valence electrons for the elements in these groups and trends in Zeff

• True

• False