combination and decomposition reactions

• In a synthesis or combination reaction, two or more simple substances combine to form a more complex substance.
• Two or more reactants yielding one product is another way to identify a synthesis reaction
• combination of a METAL with OXYGEN

  metal + oxygen → metallic oxide
• combination of a NONMETAL with OXYGEN

  nonmetal + oxygen → nonmetallic oxide
• combination of TWO METALS

  nonmetal + nonmetal → binary molecular compound
• ammonia is NH3
• combination of an ELEMENT with a COMPOUND

  element + compound → new compound
• combination of TWO COMPOUNDS (1)

  metallic oxide + water → metallic hydroxide (base)
• combination of TWO COMPOUNDS (2)

  nonmetallic oxide + water → acid
• combination of TWO COMPOUNDS

  metallic oxide + nonmetallic oxide → salt
• In a decomposition reaction, a more complex substance breaks down into its more simple parts. One reactant yields 2 or more products.
• Synthesis and decomposition reactions are opposites
• the delta above the arrow indicates that heat must be present
• in most cases, heat is used to decompose a compound. in some cases, electricity is needed for decomposition reactions to take place
• decomposition of METALLIC OXIDES

  metallic oxide → ∆ metal + oxygen
• decomposition of NONMETALLIC OXIDES

  nonmetallic oxide → ∆ nonmetal + oxygen
• decomposition of CARBONATES

  metallic carbonate → ∆ metallic oxide + carbon dioxide
• decomposition of CHLORATES

  metallic chlorate → ∆ metallic chloride + oxygen
• decomposition of BICARBONATES

  metallic bicarbonate → ∆ metallic carbonate + water + carbon dioxide
• decomposition of HYDRATES

  compound ∙ hydrate (H2O) → ∆ compound + water
• A hydrate is a hydrated salt or a compound composed of a salt chemically attached to a certain number or water molecules
• A dot (∙) is used to indicate the chemical attachment of a number of molecules of water to a salt.
• A salt to which no molecules of water are attached is called "anhydrous" salt
• 1 - mono
• 2 - di
• 3 - tri
• 4 - tetra
• 5 - penta
• 6 - hexa
• 7 - hepta
• 8 - octa
• 9 - nona
• 10 - deca
• ate - ic
• ite - ous
• ide - hydro + ic