Alkenes react by addition
| Reaction 1 | addition |  | Br2 |  |
| Reaction 2 | addition |  | HCl |  |
| Reaction 3 | addition |  | H2 with Pd catalyst |  |
| Reaction 4 | addition |  | conc H2SO4 then H2O |  |
| Reaction 5 | substitution |  | KOH in ethanol |  |
Carboxylic acids and esters react by substitution
| Reaction 6 | substitution |  | OH–(aq) followed by H3O+ |  + CH3CH2OH |
| Reaction 7 | substitution |  | CH3OH/H+ |  |
Alcohols and haloalkanes react by both substitution and elimination
| Reaction 8 | substitution |  | HBr(aq) |  |
| Reaction 9 | elimination |  | KOH in CH3CH2OH |  |
| Reaction 9 | elimination | CH3CH2CH2CH2OH | conc H2SO4 | CH3CH2CH=CH2 |