Name______
Formula of a Compound
1. Useful only if it correctly represents the substance.
2. The composition is determined in chemical analysis.
3. The formula then is derived by atomic theory and chemical bonding methods.
4. A chemical formula is a qualitative and quantitative description of the composition of a pure substance, either as element or a compound.
Naming Binary Compounds
Two types of Binary Compounds
A. Combining a metal and a non-metal 1. The metallic element is usually named and written first-this is at times called the cation. Example: KCl -The cation is K, so the name Potassium is written
2. The non-metal, which is called the anion, is made from the root word of the name of the element plus an -ide ending. Cl is chlorine, the root is chlor, then add the -ide ending to write the word chloride.
3. Place both names together: Potassium chloride
Problem Section #1
Directions: Write the non-metal ion names for the following
1. Nitrogen ______
2. Oxygen ______
3. Sulfur ______
4. Fluorine ______
5. Chlorine ______
6. Bromine ______
Problem Section #2
Directions: Write the correct names for the following Binary Compounds.
Formula Ions and charge Name KCl K+ Cl- Potassium chloride
CaCl2
AlCl3
Na2S
BaS
Al2S3
CsF
Ba3N2
MgBr2
Rb2O
Writing Chemical Formulas
1. Write the symbols to the element with the appropriate charge.
2. Cross over the number that was written as a charge.
Example Calcium chloride 2+ - Ca Cl becomes CaCl2
Problem Section #3
Directions: Write the correct formula for the following Binary Compounds.
Compound Name Ions and charge Formula Lithium chloride Li+Cl- LiCl
Barium nitride
Magnesium bromide
Sodium iodide
Strontium fluoride
Indium phosphide
Rubidium sulfide
Aluminum selenide
Cesium oxide
Francium carbide
Writing the formula for two non-metal binary compounds
With two non-metal binary compounds, the use of prefixes is necessary, for every subscript the compound name must be written with the prefix that coincides with the subscript.
Subscript Prefix Subscript Prefix
1 Mono 6 Hexa
2 Di 7 Hept
3 Tri 8 Octa
4 Tetra 9 Nano
5 Penta 10 Deca
Example Nitrogen Trioxide No prefix on nitrogen, so no subscript The prefix on oxide is Tri, so the number three will be used as a subscript
NO3
Problem Section #4
Substance Elements Prefixes Subscripts Formula Carbon tetrachloride Carbon None None
Chlorine Tetra 4 CCl4
Dinitrogen monoxide
Triphosphorus trifluoride
Sulfur dibromide
Selenium tetraiodide
Sulfur trioxide
Problem Section #5
Directions: Write the correct names for the following Binary Non-metal compounds.
Formula Element Subscript Prefix Name
N2O3 Nitrogen 2 Di Oxygen 3 Tri Dinitrogen trioxide
NO ______
______
P2O4 ______
______
NO2 ______
______
SO3 ______
______
Problem Section #6
Binary Compounds
Write the name to the formula
1. BaCl2 6. SO3
2. MgI2 7. Fr2S
3. PF 8. InF3
4. K3N 9. Cs2O
5. MgBr2 10. KCl
Directions: Write the name to the following formulas.
1. Calcium fluoride ______
2. Barium carbide ______
3. Gallium oxide ______
4. Nitrogen trifluoride ______
5. Trinitrogen dioxide ______
6. Francium iodide ______
7. Barium phosphide ______
8. Decaboron pentoxide ______
9. Sodium nitride ______
6 Binary Acids
Binary Acids start with element Hydrogen followed by a non-metal.
• The element Hydrogen is renamed Hydro • The non-metal root is then written • The root then ends with the suffix -ic.
Example: HCl Hydrogen and chlorine Hydrogen is rename Hydro The second element chlorine is written in root form, chlor The suffix -ic is now added, chloric Name Hydrochloric Acid
Problem Section #7
Directions: Write the names for the following binary compounds.
HF ______HI ______
HBr ______
Naming Binary Acids
Take the name and reference it too the elements names Write the charges Cross over the charges
Example Hydro chloric Acid Hydro-Hydrogen-H+ Chloro-Chlorine-Cl- HCl
1. Hydroiodic Acid ______2. Hydrosulfic Acid ______
7 Writing Ternary Compounds
A. Made up of three or more different elements usually one element and one polyatomic ion.
B. They are made up of metallic elements bonded to polyatomic negative ions.
C. The polyatomic ion sheet attached will be of help.
D. The following are steps in writing Ternary Compounds together.
Example: Sodium sulfite
1. Write the metallic atom symbol with its charge
Example: Na+
2. Write the polyatomic ion with its charge in parentheses.
2- Example: (SO3)
3. Multiply the metallic atom charge by the subscript on the metallic atom.
Example: +1 (x) 1 = 1 (The number of polyatomic ions)
4. Multiply the polyatomic ion charge by the subscript on the metallic atom.
Example: 2 (x) 1 = 2 (The number of metallic ions also drop the +/- signs)
5. Place both metallic and polyatomic ions together with subscripts.
Example: Na2(SO3)
6. Drop the parenthesis if there is no subscript
Example: Na2SO3
8 Problem Section #8
Directions: Write the correct formulas for the following chemical names.
Name Ion Symbol and Charge Formula 3+ - Aluminum nitrate Al (NO3) Al(NO3)3
Sodium nitrate ______
Mercury (II) cyanide ______
Cadmium (II) silicate ______
Magnesium phosphate ______
Sodium phosphite ______
Lithium tetraborate ______
Iron (III) sulfate ______
Copper (I) thiosulfate ______
Nickel (II) perchlorate ______
9 Naming Ternary Compounds
Example: Ag2(C2O4) 1. Write the metallic atom name. Ag = Silver
2. If the element is a transitional element, it will be accompanied by a Roman Numeral. The Roman Numeral will reflect the subscript on the polyatomic ion atom. Silver (I)
3. Write the polyatomic ion name
C2O4 = oxalate
4. Write both words Silver (I) oxalate
Problem Section #9
Directions: Write the correct name of the compound, when given the formula.
The metallic atom name Formula *Roman Numeral if needed/Polyatomic Ion Name
Cu(C2H3O2)2 Copper (II) /acetate Copper (II) acetate
Fe2(CrO4)3
Cu3PO4
NH4MnO4
Pb2B4O7
NaCN
Mg(ClO)2
Ga(OH)3
W(SO4)2
CaC2O4
10 All Mixed Up!!!!!!! Directions: Write the name to the following formulas.
Formula Binary/Ternary Roman Numeral Name
Cr2O3
MgCrO4
FeCl3
K3PO4
(NH4)2CO3
CaI2
BaSO4
Cu(NO3)2
Al(CN)3
CaCO3
11 Directions: Write the formula to the following chemical names.
Roman Numeral Formula Binary/Ternary if needed Formula
Lithium dichromate
Francium bromide
Indium nitrite
Tungsten (IV) iodide
Cobalt (III) sulfite
Zinc (II) selenide
Silver (I) hydroxide
Strontium peroxide
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