Chem 101 Nomenclature - Chemistry Coursescourses.chem.psu.edu/chem101/pdf's/Lectures/101Lect 6,...
Transcript of Chem 101 Nomenclature - Chemistry Coursescourses.chem.psu.edu/chem101/pdf's/Lectures/101Lect 6,...
Household Chemicals
NaHCO3 Sodium Carbonate
NaClO Sodium Hypochlorite
NH3 Nitrogen Trihydride
NaCl Sodium Chloride
H2O2 Hydrogen Peroxide
Nomenclature Terms Binary Compound contains 2 elements
Binary Ionic Compound : a metal and a nonmetal
CaCl2
Metal named first: calcium
Nonmetal named second with an –ide
ending: chloride
Name: calcium chloride
If metal has more than one charge
(transition metals) must indicate charge
with Roman numerals
I, II, III, IV, V, VI, VII
or Latin endings
-ous = lower charge
- ic = higher charge
Nomenclature Terms
Binary Covalent Compound: two nonmetals
SO2 Least electronegative element first:
sulfur Second element has -ide ending:
oxide Greek prefixes indicate subscripts 1 = mono- 6 = hexa- 2 = di- 7 = hepta- 3 = tri- 8 = octa- 4 = tetra- 9 = nona- 5 = penta- 10 = deca-
Name: sulfur dioxide
Exception: when 1st element is only a
single atom
Nomenclature Terms
Nonbinary Compound: more than 2 elements
NaOH
probably contains polyatomic ion(s)
Name the polyatomic cation first
Ionic: name metal first
sodium
Name the polyatomic anion second
hydroxide
Name: sodium hydroxide
MUST KNOW the polyatomic ions by name and formula to recognize them
Nomenclature Flow Chart
Single-Charge Multiple-Charge Metal Metal
Name the metal
Indicate metal charge by (Roman #) or Latin
name (-ous or –ic)
+ 1 nonmetal
+ 2 nonmetals
Name the polyatomic ion Nonmetal name
with –ide ending
*Metal + Nonmetal
Chemical Formula
2 Nonmetals
1) Use Greek prefixes to indicate subscripts
2) second element –ide ending
H + Nonmetal(s)
Name as acids
* Treat NH4+
as a metal when
naming compounds
NaCl: Each sodium ion has a
1+ charge and each chloride ion has a 1-
charge, so they must occur in equal numbers
to give a net charge of zero.
Determining the
Charge on a Transition Metal
Cation – Au2S3
• Determine the charge on the anion
– Au2S3: the anion is S, since it is in Group 6A, and its charge is –2
• Determine the total negative charge
– Since there are 3 S in the formula, the total negative charge is –6
• Determine the total positive charge
– Since the total negative charge is -6, the total positive charge is +6
• Divide by the number of cations
– Since there are 2 Au in the formula & the total positive charge is +6, each Au has a +3 charge
Naming of Acids
• If anion does not contain oxygen:
– Start with Hydro-
– Add –ic to the end
– Ex: HCl:
• Cl- is chloride, so the acid is Hydrochloric
acid
• If anion contains oxygen:
– Look at the ending
– If –ite, use anion root and -ous
– Ex: HNO2:
• NO2- is nitrite, so the acid is Nitrous acid
– If –ate, use anion root and -ic
– Ex: H2SO4:
• SO42- is sulfate, so the acid is Sulfuric acid