Review Ionization energy refers to how easily an atom loses an electron. Electronegativity refers to how much attraction an atom has for electrons. The presence of eight valence electrons is chemically stable (an octet). Elements tend to react to acquire that stable electron structure (of a noble gas).
Forming Chemical Bonds Chemical Bonds – The force that holds atoms together. –An ionic bond is only one type of chemical bond
Ionic Compounds The attraction between a positive ion and negative ion
Positive Ions Cations Forms when an atom loses one or more valence electron(s) in order to attain a noble gas configuration. –Example: Sodium: 1s 2 2s 2 2p 6 3s 1 Loses 1 electron to form Na + = 1s 2 2s 2 2p 6 3s 0 Neon: 1s 2 2s 2 2p 6 (the same as Na + )
Positive ion question –What noble gas configuration will a positive Mg ion have? –What will the charge be on Mg?
Negative ion –Anion –Forms when an atom gains one or more valence electron(s) in order to attain a noble gas configuration. –Example: Fluorine: 1s 2 2s 2 2p 5 Gains 1 electron to form F - = 1s 2 2s 2 2p 6 Neon: 1s 2 2s 2 2p 6
The D-Block The transition metals in the d-block are less predictable than metals and nonmetals. They tend to lose 2 or 3 electrons 2+ or 3+ charge