9.3 Naming Binary Molecular Compounds • Naming Binary Molecular Compounds • What does a prefix in the name of a binary molecular compound tell you about the compound’s composition?
9.3 Naming Binary Molecular Compounds • Carbon and oxygen combine to form carbon monoxide (CO) and carbon dioxide (CO2), but these two invisible gases are very different.
9.3 Naming Binary Molecular Compounds • Sitting in a room with small amounts of CO2 in the air would not present any problems. If the same amount of CO were in the room, you could die of asphyxiation. A naming system that distinguishes between these two compounds is needed.
9.3 Naming Binary Molecular Compounds • A prefix in the name of a binary molecular compound tells how many atoms of an element are present in each molecule of the compound.
9.3 Naming Binary Molecular Compounds • Some guidelines for naming binary molecular compounds: • Name the elements in the order listed in the formula. • Use prefixes to indicate the number of each kind of atom.
9.3 Naming Binary Molecular Compounds • Omit the prefix mono- when the formula contains only one atom of the first element in the name. • The suffix of the name of the second element is -ide.
9.3 Writing Formulas for BinaryMolecular Compounds • Writing Formulas for Binary Molecular Compounds • How do you write the formula for a binary molecular compound?
9.3 Writing Formulas for BinaryMolecular Compounds • Use the prefixes in the name to tell you the subscript of each element in the formula. Then write the correct symbols for the two elements with the appropriate subscripts.
9.3 Writing Formulas for BinaryMolecular Compounds • Silicon carbide is a hard material like diamond. The name silicon carbide has no prefixes, so the subscripts of silicon and carbon must be one. Thus, the formula for silicon carbide is SiC.
9.3 Section Quiz. • Assess students’ understanding of the concepts in Section9.3.
9.3 Section Quiz. • 1. Which of the following compounds is named INCORRECTLY? • CS2, carbon disulfide • BCl3, boron trichloride • IF7, iodine heptafluoride • PCl5, phosphorus hexachloride
9.3 Section Quiz. • 2. Which of the following molecular compounds is named INCORRECTLY? • SbCl3, antimony trichloride • C2O5, dicarbon pentoxide • CF4, carbon tetrafluoride • H3As, hydrogen arsenide
9.3 Section Quiz. • 3. The correct formula for tetraphosphorus trisulfide is • P3S4 • S3P4 • P4S3 • S4P3