Transcript Naming & Writing Formulas

Naming
&
Writing Formulas
For
Molecular & Ionic Compounds
Naming Molecular Compounds
Non-metal + Non-metal
• Step 1:
 write the element name for the first
non-metal
 add a prefix ….(if there is more than
one atom)
• Step 2:
 Write the second element name and
add an ide ending
 Add a prefix
Exceptions
• DO NOT use any prefixes at all if the first
element is hydrogen ……these are acids
Prefixes
6=
hexa
7=
hepta
3=
mono
di
tri
8=
octa
4=
tetra
9=
nona
5=
penta
10 =
deca
1=
2=
Examples
• P4O10
tetraphosphorus decaoxide
• BrH7
bromine heptahydride
• H 2S
hydrogen sulfide
Try the Following
• CO(g)
carbon monoxide
• CO2(g)
carbon dioxide
• N3F8
Trinitrogen octafluoride
Writing Formulas for Molecular
Compounds
• Steps:
 Write each elements symbol
 Write the subscript number (the prefix)
• E.g.
 dinitrogen oxide
N2O
 Sulfur dioxide
S20
Try the Following
• oxygen dibromide
OBr2
• diphosphorus pentasulphide
P2S5
• carbon tetraiodide
CI4
• phosphorus pentachloride
PCl5
Molecular Compounds that Must be memorized !!!
NH3 ( g) = ammonia
H2O ( l) = water
H2S ( g) = hydrogen sulphide
CH4 ( g) = methane
CH3OH ( l) = methanol
C2H6 ( g) = ethane
C2H5OH ( l) = ethanol
C6H12O6 ( s) = glucose
C12H22O11 ( s) = sucrose
O3 ( g) = ozone
H2O2 ( l) = hydrogen peroxide
Naming Binary Ionic
Compounds
Metal + non-metal
• DO NOT USE PREFIXES
• Steps
1.Write the metal 1st
2. Write the non-metal 2nd with an ide
ending
E.g.
NaF sodium fluoride
Na2S sodium sulphide
two sodium ions are bonded with
one sulphide ion… this doesn’t
matter for naming ionic compound
Try the Following
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LiF
KCl
BeS
Rb3P
MgF2
Na2O
CsBr
lithium fluoride
potassium chloride
beryllium sulphide
rubidium phosphide
magnesium fluoride
sodium oxide
cesium bromide
Try the Following
• KCl
potassium chloride
• MgBr2
magnesium bromide
• Ba3N2
barium nitride
• ScP
scandium phosphide
Writing Formulas for Binary
Ionic Compounds
• Steps
1.Look up the symbol for each…& write the
metal first
2.Balance the charges
(total + charges = total – charges)
3.Use subscripts to show the # of each
element
sodium oxide
1+
2  Charge
Charge
1+  2 = 2 +
2  1 = 2
Na2O
calcium phosphide
2+
Charge
2+
3=
3  Charge
32=6
6+
Ca3P2
Try the Following
• magnesium chloride
MgCl2
• calcium chloride
CaCl2
• zinc sulphide
ZnS
• silver sulphide
Ag2S
• germanium oxide
GeO2
• calcium arsenide
Ca3As2
• magnesium nitride
Mg3N2
Try the Following
• lithium iodide
LiI
• zinc fluoride
ZnF2
• strontium phosphide
Sr3P2
• silver oxide
• germanium arsenide
Ag2O
Ge3As4
Naming Multivalent Ionic
Compounds
transition metal + non-metal
• Transition metal ions have more than one
possible charge
Cu2+, Cu+, Fe3+, Fe2+
• Steps
1. Write metal 1st with the charge in roman
numerals
Roman Numerals (I,II,III,IV,V,VI,VII)
2.Write non-metal second
remember the charges have to balance
Examples
uranium (VI) fluoride
U6+
F–
UF6
chromium (III) nitride
Cr3+
N3-
CrN
cobalt (II) chloride
Co2+
ClCoCl2
Try the Following
• AuBr
gold (I) bromide
• CrCl2
chromium (II) chloride
• Co2O3
cobalt (III) oxide
• VS2
vanadium (IV) sulphide
• PuN2
plutonium (VI) nitride
Naming Complex Ions
Metal + complex ion
• Steps:
1. Name the metal ion
2. Name the complex ion
E.g.) PO43
Note: NH4+ (ammonium ion) is the
only positive complex ion…it
will take the place of a metal
Examples
• CaCO3
• Ba(OH)2
• (NH4)3N
Solutions
• CaCO3
Calcium carbonate
• Ba(OH)2
Barium hydroxide
• (NH4)3N
Ammonium nitride
Try the Following
• KIO3
potassium iodate
• NaCH3COO
sodium acetate
• MgSO3
magnesium sulphite
• NH4NO3
ammonium nitrate
• Ca3(PO4)2
calcium phosphate
Writing Formulas For Complex
Ions
• Steps:
1. Look up the symbol for each ion
2. Balance the charges
• Note: if you need more than 1 complex ion
to balance the charges use brackets
2+
1-
• E.g. Ca(CH3COO)2
Try the Following
• aluminum phosphate
AlPO4
• calcium sulphite
CaSO3
• scandium acetate
Sc(CH3COO)3
• ammonium sulphate
• nickel (II) phosphate
• aluminum chlorate
(NH4)2SO4
Ni3(PO4)
Al(ClO3)3
2
Solubility
Will the compound dissolve in water?
Soluble
• Refers to whether or not the compound
dissolves in water
• If it is…. the compound is aqueous (aq)
• All acids are soluble
• Some ionic compounds are soluble… the
rest are solids
Is It soluble?
• This will apply to ionic compounds (only)
• Steps
1. Find each ion in the boxes across the
top
2. if it is soluble it will have (aq) aqueous
3. If it does not dissolve it will have (s)
solid.
Determine if the following compounds are
soluble in water. Use the proper subscript
to indicate the state.
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AgCl
BaCO3
LiOH
Ca2(PO4)3
NaCl
CaI2
Pb(NO3)2
HMnO4
• AgCl
(s)
• BaCO3
(s)
• LiOH
(aq)
• Ca2(PO4)3 (s)
• NaCl
(aq)
• CaI2
(aq)
• Pb(NO3)2
(aq)
• HMnO4
(aq)
Acids & Bases
Acids
• They are always soluble in water
• Conduct electricity
• Taste sour
• React with metals to produce hydrogen
gas (H2(g))
• Neutralize a base
• they ALWAYS have hydrogen ….usually
as the first element
• E.g. HCl(aq) , H3PO4(aq)
• There are three types:
 Binary
 Oxo
 Organic
Binary Acids
• contain only H and one other element (Cl,
Br, etc.)
• E.g. HCl (aq)
Oxo Acids
• Contain H and Oxygen
• E.g. H3PO4(aq)
Organic Acids
• Contain C, H, & O
• The H is written at the end
• All have COO• E.g. CH3COOH(aq) – acetic acid
C6H5COOH(aq) - benzoic acid
HOOCCOOH(aq) – oxalic acid
Acid Indicators
• Turns blue litmus paper red
• Able to turn bromothymol blue to yellow
• Phenolphthalein remains
colorless
• E.g. lemon juice
Bases
• Are usually soluble in water
• Conduct electricity (not weak ones)
• Neutralize acids
• Taste bitter
• Usually solids
• Feel slippery
Base Indicators
• Turns red litmus paper blue
• Bromothymol blue remains blue
• Turns phenolphthalein pink
• E.g. baking soda, Rolaids,
soap, Draino crystals
Naming Acids
• Steps:
 Hydrogen ____ide becomes hydro____ic acid
 Hydrogen ____ate becomes _______ic acid
 Hydrogen ____ ite becomes _______ ous acid
Examples
• HF (aq)
hydrogen fluoride = hydrofluoric acid
• H2SO3 (aq)
hydrogen sulphite = sulphurous acid
• H3BO3 (aq)
hydrogen borate = boric acid
• HCl (g)
Hydrogen chloride (not an acid)
Try the Following
hydrosulphuric acid
phosphorus acid
carbonic acid
hydrogen sulphide
1+
2-
H2S (aq)
hydrogen phosphite
1+
3-
H3PO3 (aq)
hydrogen carbonate H2CO3(aq)
1+
2-
Writing Acid Formulas
• Steps:
1. Use the naming rules in the opposite
direction
• Example:
hydrosulphuric acid hydrogen sulphide H2S(aq)
Try the Following
• carbonic acid hydrogen carbonate H CO
2
3(aq)
• chlorous acid hydrogen chlorite
HClO2(aq)
Naming Bases
• Steps:
1. Write the metal name 1st
2. Write hydroxide or bicarbonate
E. g.
NaOH
sodium hydroxide
Try the Following
• KOH
• Ba(OH)2
• NaHCO3
potassium hydroxide
barium hydroxide
sodium bicarbonate
Chemical Reactions
• Can cause a physical or a chemical
change
• Always results in the formation of a new
substance
• Evidence:
1. Temperature change
2. Formation of a precipitate
3. Colour change
4. Gas produces
Reactants
Products
balancing
1 Zn(s) + 2 HCl(aq)
states
1 ZnCl2(aq) + 1 H2 (g)
states
Energy Changes
• Can occur in the form of heat, light,
electrical, or mechanical
• There are two types:
 Endothermic
 Exothermic
• Endothermic
 Energy is absorbed (enters)
 Reactants + Energy
products
• Exothermic
 Energy is released (leaves)
 Reactants
product + energy
Balancing Equations
• There must be equal numbers of each
element on both sides of the equation
Use lowest numbers
Example
____Mg(s) + ___ O2(g)  ___ MgO(s)
____ H2O(l)  ____H2(g) + ____ O2(g)
• When chemicals react they follow the Law
of Conservation of Matter:
 Matter can not be created or destroyed
it only changes form
• Mass of reactants = mass of products
Counting Practice
• How many of each element are in the
following compounds?
1. NaCl
5. NH4CH3COO
2. BaBr2
6. 3 (NH4)2S
3. (NH4)3P
7. 2 CaCl2
4. Ba(OH)2
8. 8 PbI2
9. 4 Zn(CH3COO)2
Balancing Practice
____ Cu(s) + ____ AgNO3(aq)  ____ Ag(s) + ___Cu(NO3)2(g)
___ Cl2(g) + ____ NaBr(aq)  ____ Br2(l) + ____ NaCl(aq)
____ KI(aq) + ___ Pb(NO3)2(aq)  ___ PbI2(s) + ___KNO3(aq)
____ CH4(g) + ____ O2(g)  ____ CO2(g) + ____ H2O(g)