Chemical Bonds. 6-1 Ionic Bonding. When is an atom unlikely to react? What is one way in which elements can achieve stable electron configurations? How does the structure of an ionic compound affect its properties?. Stable Electron Configurations.
Chlorine to Argon
Sodium to Neon
Negative charge - anion…suffix = ide
Positive charge – cation… just use element name
Crystals: solids arranged in a lattice structure
The properties of an ionic compound can be explained by the strong attractions among ions within a crystal lattice.
Class Participation Opportunity: Research report on how to make rubies
Many nonmetal elements exist as diatomic molecules (two atoms).
The space-filling models show that orbitals of atoms overlap when they form covalent bonds.
The different sizes of spheres model the different atomic radii of the atoms.
Generally, elements on the right and on the top of the periodic table have a greater attraction for electrons that elements on the left (except noble gases).
There are forces of attraction between molecules but they are not as strong as the attractions between ionic and covalent bonds. They are strong enough to hold the molecules together in a liquid or solid.
Can be mixed with paint for whitewashing
The vase and the plate are both coated in oxides of copper (copper and oxygen), one red and one black.
Calling both oxides by the same name won’t work, so there must be two names.
Binary Ionic Compounds
A compound made from two elements is a binary compound.
The name of the cation is followed by the name of the anion.
cation = metal without any change
sodium atom and sodium ion
anion = uses part of the name of the nonmetal with the suffix ide
iodine atom and iodide ion
CuO→ Cu2+ + O2-
that has a positive or negative charge on
and acts as a unit is a polyatomic ion.
indicates that there are three hydroxide ions
for each iron (III) ion.
Two Na (Na+) for each S(S2-)
Even though the electrons are moving among the atoms, the total number of electrons does not change so the metal is neutral.
The more valence electrons an atom can contribute to the pool, the stronger the bond will be.
alkali metal = weak bond (1 valence electron), soft with low melting point
transition metal = stronger bond )more valence electrons), harder with higher melting points