Chemical Nomenclature and Formulas: What’s in a Name?
LOL
ASAP
FYI
BRB
Binary Compounds—Writing Chemical
formulas
1) Cation, Anion
2) Write oxidation number/charge on each element.
3) Balance charges by the smallest common multiplier between the two elements. Charges must add to 0 for a neutral compound.
4) Add the subscripts for each element in the chemical compound.
Example 1: Magnesium bromide
Example 2: Aluminum oxide
5) If the first element is a transition element, the oxidation number or charge of the element is given by a Roman numeral (I, II, III, IV, etc.) following the element name. Exceptions: Ag+1 and Zn+2—they will always have these charges.
Example 3: Tin (IV) sulfide
Example 2: Mercury (II) fluoride
Example 4: Iron (III) oxide
Try…..1)Calcium chloride
2)Copper (I) oxide
3)Sodium bromide
4)Potassium sulfide
5)Calcium oxide
Binary Compounds—Writing Chemical formulas (Cont.)
6) If a binary compound has a prefix or prefixes in front of an element name, these prefixes are the subscripts for that element in the chemical formula. Prefixes represent the number of element atoms present in a molecule of the chemical compound.
Prefixes
1 mono 6 hexa
2 di 7 hepta
3 tri 8 octa
4 tetra 9 nona
5 penta 10 deca
Example 1: Carbon tetrachloride
Example 2: Diphosphorus
trioxide
Polyatomic Chemical Compounds—Writing Chemical Formulas.
1) Cation, Anion—reference table
2) Write the oxidation number/charge on each element and polyatomic ion.
3) Balance charges by the smallest common multiplier between the cation and anion. Charges must add to 0 for a neutral compound.
4) Add the subscripts for each element/polyatomic ion to the chemical compound.
*Polyatomic ions: place polyatomic ions in parentheses when adding subscript (ex. (NO3)2)
Example 1: Silver nitrate
Example 2: Magnesium acetate
Example 3: Calcium carbonate
Example 4: Ammonium chloride
Can we go in
reverse?
Binary Compounds: Chemical
Nomenclature1) Write an element’s oxidation number over the element symbol.
2) Cation, Anion—write the element name
3) Add the ending -IDE to the second element/anion
Example 1: Al2S3
Example 2: CaBr2
Transition Elements
4) Place a Roman numeral matching the charge/oxidation # on an element after the positive element’s name. Roman numeral is put in () (ex. (II)). Roman numeral indicates the oxidation number on an element can vary.
-Go back to Step #3
Example 1: CuS
Example 2: CoBr2
5) If both elements are found on the RIGHT side of the periodic table, use the appropriate prefix for a given element.
-Go back to Step #3
Example 1: SBr3
Example 2: CCl4
Compounds with Polyatomic Ions:
Chemical Nomenclature
1) Write oxidation # for each element/polyatomic ion in the formula
2) Write the element and/or polyatomic ion names.
3) If a transition element (an element where the oxidation # varies), use a Roman numeral to indicate an element’s oxidation # in the chemical name.
*NO –IDE ENDING!!!!
Example 1: Sr(NO3)2
Example 2: CuSO4
Homework 9/25
Inorganic Nomenclature worksheet
Read over lab procedure for Thursday
Liquid Chromatography Lab due Thursday
Study for Element/Polyatomic quiz next Tuesday, October 3rd