Reaction

Acetaldehyde

Acetone

Similarities

1. Reduction with H₂ and Ni or LiAlH₄             

Forms ethyl alcohol

Forms isopropyl alcohol

2. Clemmensen's reduction

(Zn/Hg and conc. HCl)

Forms ethane (an alkane)

Forms propane (an alkane)

3. Addition of HCN

Forms acetaldehyde cyanohydrin

Forms acetone cyanohydrin

4. Addition of NaHSO₃

White crystalline derivative

White crystalline derivative

5. Grignard reagent followed by hydrolysis

Forms isopropyl alcohol

Forms tertiary butyl alcohol

6. With hydroxylamine

      (NH₂OH)

Forms acetaldoxime  (an oxime)

Forms acetoxime (an oxime)

7. With hydrazine (NH₂NH₂)

Forms acetaldehyde hydrazone

Forms acetone hydrazone

8. With phenyl hydrazine (C₆H₅NHNH₂)

Forms acetaldehyde phenylhydrazone

Forms acetone phenyl hydrazone

9. With semicarbazide

(H₂NNHCONH₂) 

Forms acetaldehyde semicarbazone

Forms acetone semicarbazone

10. With PCl₅

Forms ethylidene chloride (Gem dihalide)

Forms isopropylidene chloride (Gem dihalide)

11. With chlorine

Forms chloral (Gem trihalide)

Forms trichloro acetone (Gem trihalide)

12. With alcohols

Forms acetal (a diether)

Forms ketal (a diether)

13. With SeO₂

Forms glyoxal

Forms methyl glyoxal

14. Iodoform reaction

      (I₂ + NaOH)

Forms iodoform

Forms iodoform

15. Bleaching powder

Forms chloroform

Forms chloroform

16. Aldol condensation with mild alkali

Forms aldol

Forms diacetone alcohol

17. Polymerisation

Undergoes polymerisation

Does not undergo polymerisation but gives condensation reaction

18. With NH₃

Forms acetaldehyde ammonia

Forms diacetone ammonia

19. With conc. NaOH

Forms brownish resinous mass

No reaction

20. With HNO₂

No reaction

Forms oximino acetone

21. With chloroform

No reaction

Forms chloretone

22. With alk. sodium nitroprusside

Deep red colour

Red colour changes to yellow on standing

23. With sodium nitroprusside + Pyridine

Blue colour

No effect

24. Boiling point

21^o C

56^o C

Dissimilarities

25. With Schiff's reagent

Pink colour

Does not give pink colour

26. With Fehling's solution

Gives red precipitate

No reaction

27. With Tollen's reagent

Gives silver mirror

No reaction

28. Oxidation with acidified

K₂Cr₂O₇

Easily oxidised to acetic acid

Oxidation occurs with difficulty to form acetic acid