Binary Molecular Compounds: Compounds made by two different nonmetals. Examples: CO2 HBr P2O5

Naming Binary Molecular Compounds: 1)The first element in the formula is always named first, using the entire element name. 2) The second element in the formula is named using the root of the element & adding the suffix –ide. 3) Prefixes are used to indicate the number of atoms of each type that are present in the compound.

Prefixes # of atoms Mono ----------- one Di ---------------- two Tri --------------- three Tetra ----------- four Pent ------------ five Hex ------------- six Hept –---------- seven Oct ------------- eight Non ------------- nine Dec ------------- ten

Naming Binary Molecular Compounds: EXAMPLES: N2O5 – H2O -- N2O -- CO2 -- PCl5 -- SO3 -- NH3 -- dinitrogen pentoxide. dihydrogen monoxide. dinitrogen monoxide. carbon dioxide. phosphorus pentachloride. sulfur trioxide. nitrogen trihydride.

Writing Formulas (Molecular Compounds): 1) Write the element symbols in the same order than it appears in the compound name. 2) Use subscripts to represent the number of atoms of each element indicated by the prefix used. Dinitrogen tetroxide ------ Dihydrogen monoxide ------ Diphosphorus monoxide ---- Carbon monoxide ------------ Phosphorus trichloride ----- N2O4 H2O P2O CO PCl3

Practice: 1) CCl4---- 2) Phosphorus tribromide –- 3) CO ----- 4) Dichlorine pentoxide ---- 5) HI(g) --- 6) Hydrogen chloride--- Carbon tetrachloride. PBr3 Carbon monoxide. Cl2O5 Hydrogen iodide. HCl(g)