Molecular Compounds Mr. MacMillan

Naming Binary Ionic Compounds There are two ways to identify a compound: Chemical Name Chemical Formula IUPAC International Union of Pure and Applied Chemistry Binary Ionic Compounds Compound composed of a metal cation and a non-metal anion

Rules for Naming The first part of the name always identifies the positive ion, which is the metal cation. Thus, this part of the name is the name of the metal. The second part of the name always identifies the negative ion, which is the non-metal anion. The name of the non-metal ion always ends with the suffix ide.

Blue – Metals Teal – Non-metals Light Purple - Metalloids

Examples Magnesium and Phosphorus Sodium and chlorine Magnesium phosphide Sodium and chlorine Sodium chloride

Determining the Chemical Formula Cross-over method Identify the metal and non-metal Write the symbols Write the charges Cross over the charges from top to bottom Remove the charge Simplify the numbers and remove the 1’s

Electron Dot Diagram and Bohr-Rutherford Electron Dot (Only showing valence electrons)

Multivalent Metals Metals that have more than one ion charge listed in the periodic table. They can form different Ions depending on the chemical reaction Examples: Copper, Lead, Tin, Iron

Ionic Compounds with Polyatomic Ions An ion that is composed of more than one atom. Ternary compound A compound composed of three different elements Most end in ite or ate

Molecular Compounds Also known as covalent compounds, are usually composed of two or more different non-metals Atoms share a pair of electrons to form a covalent bond The stability is associated with a full outer energy level of electrons

Molecules A neutral particle composed of two or more atoms joined together by covalent bonds The term molecule is also used to describe two or more atoms of the same element. H2 O2

Naming Binary Molecular Compounds A compound composed of two non-metals joined by one or more covalent bonds. Prefix Number Mono 1 Di 2 Tri 3 Tetra 4 Penta 5 Hexa 6 Hepta 7 Octa 8

How to Name Binary Compounds Count the number of atoms of the first element in the chemical formula Write the appropriate prefix followed by the name of the element (mono is never used for first element) Count the number of atoms of the second element in the chemical formula Write the appropriate prefix followed by the name of the element using the suffix ide. If the prefix ends with a or o, this letter is dropped before oxide

Your Turn CS2 CCl4 Si2 Br6 Answers Carbon disulfide Carbon tetrachloride Disilicon hexabromide

Writing Chemical Formulas Write the chemical symbol of the 1st element Determine the number of atoms of the 1st element based on the prefix. Write the chemical symbol of the second element. Determine the number of atoms of the 2nd element based on the prefix. Write the chemical formula for the compound, using the appropriate subscripts.

Your Turn Answers NF3 SF2 P2 O6 Write the chemical formula for each binary molecular compound. Nitrogen trifluoride Sulfur difluoride Diphosphorous hexoxide Answers NF3 SF2 P2 O6