Question

IS there a quick and easy way to write chemical equations or are most of them just memorized and known?

Answer 1

most chemical reactions fall under one of 5 distinct patterns, and those you should set out to memorize:

synthesis: A + B \(\rightarrow\) AB

decomposition: AB \(\rightarrow\) A + B

single displacement: A + BC \(\rightarrow\) B + AC

double displacement: AB + CD \(\rightarrow\) AD + CB

combustion: \(C_xH_z\) + \(O_2\) \(\rightarrow\) \(CO_2\) + \(H_2O\)

the reactions aren't balanced, but that's easily done once you recognize the format