Balancing/writing/ identifying chemical equations and reactions

SynthesisA+B–> AB
2Na + S= 2NaS
DecompositionAB–> A + B
Compound- element + element or compound
You’ll always get a gas
Single displacementA + BC–> B + AC
Element + Compound = new element + new compound
Double displacementAB + CD = CB + AD
Compound + compound = new compound + new compound
CombustionCxHy + O2–> Co2 + H2O
ALWAYS
Diatomic elements?Heavy Norwegian Oldenburgs Face Clearly Brawny Incidents