bonding and properties

A=P=E M-A=N

-Atomic number=Protons=Electrons
-Mass Number-Atomic number=neutrons
-mass number=atomic number+neutrons

in ion-electron equations, gain of electrons go on...

reaction side

in ion-electron equations, loss of electrons go on...

product side

Covalent molecular properties

-small molecules (discrete)
-cannot conduct electricity-don't have any free particles which are free to move
-fixed number of atoms
-soluble(*like dissolves like)
-low mp/bp
-weak attractions between molecules

covalent network properties

-big
-very strong
-very high mp/bp (strong bonds must be broken)
-insoluble
-cannot conduct electricity(except graphite)-have to free electrons to carry charge
-contain carbon(graphite, diamond), boron or silicone

structures

-tetrahedral
-trigonal pyramidal
-angular
-linear

covalent bonds

-formed when two positive nuclei are held together by their common attraction for a shared pair of electrons
-strong bond
-non metals

ionic bond

force of attraction between the positive and negative ions (metals & non-metals)

properties of ionic compounds

-soluble in water + ionic substance
-SOLIDS DON'T conduct electricity
-liquid & molten conduct as ions are free to move

non-metal atoms will...

gain electrons to form negative ions

metal atoms will...

lose electrons to form positive ions

prefix rule

mon-1
di-2
tri-3
tetra-4
penta-5
hexa-6

Valency Rule

s-symbol
v-valencies
s-swap
d-divide
f-formula

single covalent bond

sharing 1 pair of outer electrons, H-H

double covalent bond

sharing 2 pairs of outer electrons, O=O

group ions

ions that contain more than type of atom

negative ions

-formed when non metal atoms gain electrons
-atoms that gain electrons have more negative electrons than positive protons and so have a negative charge

positive ions

-formed when metal atoms lose electrons
-atoms that lose electrons have more positive protons than negative electrons and so have a positive charge

ionic bond

-positive and negative ions are strongly attracted to each other, this is called electrostatic attraction
-very strong bonds

ionic structure

-ionic compounds form a lattice structure of oppositely charged ions(held together by electrostatic forces)
-all ionic compounds are solid at room temp. bc the ionic bonds in the lattice are very strong

ionic compound properties

-high mp/bp because strong bonds must be broken
-dissolve in water and ionic solutions
-solids DO NOT conduct
-liquid/molten DO conduct as ions are free to move

when writing ionic formula

include charges