topic 3.0 – chemical compounds. chemical compounds element – simplest form of matter; cannot be...
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Topic 3.0 – Chemical Compounds
Chemical Compounds
Element – simplest form of matter; cannot be broken down any further
Ex. Au, carbonCompound – formed from two or more
elements Can be separated into its elements by using electricity Ex. NaCl, H20
Compounds
There are 2 types of compounds:1) Ionic compounds2) Molecular Compounds
Each compound can be represented by its name or chemical formula
Chemical formula – symbols and numbers representing which atoms and how many are in the compound
Fill out the chart.
Elements # of Atoms of each element
Total # of atoms
H20
NaCl
MgCl2
Fe2O3
IUPAC – international union of pure and applied chemistry
-creates rules for naming compounds
Ion- is an atom that has lost or gained has lost or gained electronselectrons; it is a charged atom
-ions are formed only when metals and non-metals are dissolved in water or in an ionic compound**
A. Ionic Compounds
*A compound that is formed from a metal ion metal ion and a non-metalnon-metal ion.*
Properties of Ionic CompoundsHigh melting point (are usually solids)Good conductivity when melted or dissolved
in waterSolids are crystal shapeBreak into ions when dissolved in water
A. Ionic Compounds
Naming :1.Name the metal ion first.2.Name the non-metal second.3.Write in all lowercase letters4.Change the ending of the non-metal to –ide.
A. Ionic Compounds
Ex. BaCl2
Ex. K2S
Ex. Sr3P2
Ex. AlP
Ex. ZrO2
Ex. Li2S
A. Ionic Compounds
Formulas:1.Write down the metal and non-metal symbols
and charges.2.Balance the + and – charges by adding ions.3.Write the metal symbols first. Write the
number of metal atoms needed as a subscript.
4.Write the non-metal symbols second. Write the number of the non-metal atoms needed as a subscript.
Ionic Compounds
Ex. barium sulphide
Ex. potassium oxide
Ex. Calcium nitride
Ionic Compounds
Ex. Aluminum chloride
Ex. Sodium oxide
Ex. Silver chloride
Ionic Compounds
Multivalent ions Multivalent ions are those metal atoms that have 2 or more charges listed Ex. Sn2+ or 4 +, Pb2 + or 4 +
-when you name compounds with these, you MUST write down which charge is being used using roman numerals.
I – one, II – two, III – three, IV- four, V-fiveVI - six
Ionic compounds
FeCl3
Fe2O3
NiS
CuCl
CuBr2
PtO2
Molecular Compounds
A compound made from >2 non-metal atoms (no metals)
Properties of Molecular CompoundsAre solid, liquid or gas at room tempDo not conduct (are insulators)Low melting and boiling pointsEx. Sugar, H20, CO2
Molecular Compounds
Naming1.Write down the prefix of the first atom
(except –mono).2.Write down this atoms name.3.Write down the second atoms prefix (all).4.Write down this atoms name. Change ending
to –ide.
Molecular compounds
Prefixes – must memorize1- mono2- di3-tri4- tetra5 - penta
Molecular Compounds
Ex. CO2
Ex. CO
Ex. N2O
Molecular Compounds
CCl4
SF5
N2O3
Molecular Compounds
Writing the Formula1. Write down the atom name and its prefix.
Molecular compounds
Ex. sulphur dibromide
Ex. silicon tetrafluoride
Ex. phosphorus trichloride
Common Molecular Compounds
These compounds are used so often they have common names:
> ammonia NH3 > water H20 > glucose C6H12O6 > hydrogen peroxide H2O2 >
Ionic or Molecular?
Ex. AlCl3
Ex. NaCl
Ex. SO3
Matching
Match the name to the unknown substance: sodium chloride or sulphur dioxide
Melting Point Conductivity State
Identity
#1 high High Solid
#2 Low Low Gas