2-nitropropane
2-propylene
2T
2-trichloro-1
2'-trifluoroethane
360-degree
3-axis
3-butylene
3-D
3D
  3-dimension
3H
3-methyl-1-pentyn-3-ol
3-methyl-2-butene
3-pole
3-position
4-acetyl-6-tert-butyl-1
4'-diisocyanate
4-dioxane
4fo
4-strand