How can you know when an equation is (s),(d),(sr),(dr)or (c)?

s-synthesis d-decomposition sr-single replacement dr- double replacement or c- combustion

How can you know when an equation is (s),(d),(sr),(dr)or (c)?
You have to look at the products and reactants.


Synthesis is when two elements come together to make a compound, or when two simpler compounds come together to form another compound:


Na + Cl -%26gt; NaCl





Decomposition is just the opposite. Its when A compound is broken down, into elements or simpler compounds:


NaCl -%26gt; Na + Cl





Single replacement is when one element replaces another in a compound. I like to think of it as a marriage, where one element (the one with higher activation energy) replaces the other.


Na + LiCl -%26gt; NaCl + Li





Double replacement is similar to sr, only its more like a california marriage, where everyone simply switches partners:





NaCl + LiBr -%26gt; NaBr + LiCl





Combustion something is burned (always in the presence of excess oxygen) to form carbon dioxide and water:





CH4 + 2O2 -%26gt; CO2 +H2O