In chemistry, compounds are substances that are made up of two or more different types of atoms chemically bonded together. When we name compounds, we use a set of rules to ensure that each compound has a unique name that accurately reflects its chemical composition.
The International Union of Pure and Applied Chemistry (IUPAC) has developed a set of rules for naming compounds that is widely used in the scientific community. This system is known as IUPAC nomenclature.
Binary compounds are compounds that contain only two types of atoms. When naming binary compounds, the first element in the compound is named first, followed by the second element with the suffix “-ide”. For example, if we have a compound made up of sodium and chlorine, we would name it sodium chloride.
If the first element can have more than one possible charge, we use Roman numerals to indicate the charge of the ion. For example, iron can have a charge of either 2+ or 3+, so we would name FeCl2 as iron(II) chloride and FeCl3 as iron(III) chloride.
Ternary compounds are compounds that contain three or more types of atoms. When naming ternary compounds, we first name the cation (the positively charged ion) and then the anion (the negatively charged ion).
If the cation can have more than one possible charge, we use Roman numerals to indicate the charge of the ion. If the anion is a polyatomic ion (an ion made up of two or more atoms), we use the name of the polyatomic ion. For example, if we have a compound made up of calcium, carbon, and oxygen, we would name it calcium carbonate.
Practice Naming Compounds
Let’s practice naming some compounds using IUPAC nomenclature:
- NaCl Answer: Sodium chloride
- FeCl2 Answer: Iron(II) chloride
- CaCO3 Answer: Calcium carbonate
- NH4OH Answer: Ammonium hydroxide
- K2SO4 Answer: Potassium sulfate
Naming compounds is an important part of chemistry. By following the rules of IUPAC nomenclature, we can ensure that each compound has a unique name that accurately reflects its chemical composition.