IONIC BONDING. The Metal – Nonmetal Bond. Lewis Dot Structures. A famous chemist named Lewis invented a symbol to show valence electrons. He used a dot next to the symbol to represent each valence electron. The dots are spread around the 4 sides. Each pair of dots Represents a bond.
The Metal – Nonmetal Bond
Represents a bond.
OH-1 = hydroxide
NO3-1 = nitrate
PO4-3 = phosphate
SO4-2 = sulfate
just like single atom
ions.Polyatomic ions: are groups of atoms bonded together with a charge hence the name “poly” “atomic” “ions”.
+2 -1(2) = 0
strontium nitrate = Sr(NO3)2
+2 + -1(2)
lithium phosphate Li3PO4
+1(3) + -3 = 0
potassium sulfate = K2SO4
+1(2) + -2 = 0
Lead (IV) hydroxide
Iron (III) sulfate Fe2(SO4)3
Some ionic compounds absorb water molecules into their structures. These are called hydrates. NaCl•2H2O is the symbol for sodium chloride dihydrate. Notice the prefix di- means 2 water molecules.
Name these hydrates: MgSO4•5H2O
You can find the percentage of water in a hydrate by dividing the mass of the water by the total mass times 100.
Lets take NaCl•2H2O
Using the periodic table, the mass of Na=23, Cl=35.5, H2O = 18. Total mass with 2 H20 is 94.4
Water mass (36)/ Total (94.4) x 100
= 38 % water
If Miley says it’s hot, it’s HOT!
Covalent Bonds can have multiple bonds, so you should be familiar with the following…
Single Covalent Bond- chemical bond resulting from sharing of an electron pair between two atoms. H2O
Double Covalent Bond- chemical bond resulting from sharing of two electron pairs between two atoms. CO2
Triple Covalent Bond-chemical bond resulting from sharing of three electron pairs between two atoms. N2
0 .4 2.0
A nonpolar bond tends to share electrons equally
A polar bond means there is a dipole or one pole (end) with a positive charge and one pole (end) with a negative charge, therefore they tend to stick together better since their opposite charges attract. (=)(-)
Very strong polar bonds are
ionic bonds like NaCl