1. $RCHO+H_2\xrightarrow{{Ni, t^o}} RCH_2OH$
2. $2CH_3COOH+2Na\to 2CH_3COONa+H_2$
3. $HCOOH+KOH\to HCOOK+H_2O$
4. $CH_3COOH+C_2H_5OH\buildrel{{H_2SO_4 đ, t^o}}\over\rightleftharpoons CH_3COOC_2H_5+H_2O$
5. $RCOOH+ROH\buildrel{{H_2SO_4 đ, t^o}}\over\rightleftharpoons RCOOR+H_2O$
6. $RCHO+2AgNO_3+3NH_3+H_2O\to RCOONH_4+2Ag+2NH_4NO_3$