Synthesis Reactions What is a Synthesis Reaction? -Two smaller pieces join together to produce a larger, more complex compound -A + B AB -Must use same cross charge rules from previous chapter -Do not forget BrINClHOF – only exist in diatomic states -Example : Iodine – I2 at all times – use this during reactions and crossing charges Synthesis with Halogens -Alkali Metal with Halogen: Find charges from periodic table/required ions chart, add elements together, cross charges -Example: Li + Br LiBr (Li +1, Br -1) -Alkaline Earth Metal with Halogen: Find charges from periodic table/required ions chart, add element together, cross charges, PATTERN: two Halogen for one Alkaline Earth Metal -Example: Mg + Cl MgCl2 (Mg +2, Cl-1) -Transition Metal with Halogen: Find charges from periodic table/required ions chart, add elements together, cross charges, use roman numerals, simplify subscripts -Example: Fe + I2 FeI3 Synthesis with Oxidation (Oxygen/Sulfur) - Element + oxide (O2) - Alkali Metal with Oxide: Find charges from periodic table/required ions chart, add elements together and cross the charges; have two Alkali Metal ion to one Oxygen/Sulfur o Example: Na + O2 Na2O - Alkaline Earth Metal with Oxgyen: follow above process and naming rules from Halogen synthesis; always have one of each ion o Example: Mg + O2 MgO - Transition Metal with Oxygen: follow normal rules for naming Transition Metals, depends on the charge of the Transition Metal o Example: Fe + O2 Fe2O3 - Nonmetal with Oxygen: when combined, nonmetallic oxide is formed o Example: C + O2 CO2 Synthesis of Metal-Oxides with Water -Alkali Metallic Oxide with Water: follow naming rules, forms a metal hydroxide of an ion - Metal hydroxide is a metal and a hydroxide -Example: Na2O + H2O NaOH - Alkaline Earth Metallic Oxide with Water: follow naming rules, forms a metal hydroxide of an ion with one metal ion and two hydroxide ions -Example: MgO + H2O Mg(OH)2 -Transition Metallic Oxide with Water: follow naming rules, forms a metal hydroxide, the ion number depends on the charge of the transition metal -Example: Fe2O3 + H2O Fe(OH)3 -Nonmetallic Oxide with Water: follow naming rules, forms a non-metallic hydroxide -Example: CO2 + H2O H2CO3