The EFFECT of the conjugated nitro-olefin group on various physical properties has been determined. The boiling points at 10 mm. and the refractive indices and densities at 30°, 40°, and 60°C. were measured for a series of 21 conjugated linear nitro-olefins having straight-chain 22 Nitroethylene 35 4-Methyl-3-nitro-2-pentene 23 1-Nitropropene 36 2,3-Dimethyl-l-nitro-1-butene 24 2-Nitropropene 37 1-Nitro-l-heptene 25 1-Nitro-l-butene 38 2-Nitro-l-heptene 26 2-Nitro-l-butene 39 5-Methyl-3-nitro-3-hexene 27 2-Methyl-l-nitro-l-propene 40 1-Nitro-l-octene 28 1-Nitro-l-pentene 41 2-Methyl-3-nitro-3-heptene 29 2-N itro-1 -pentene 42 4-Ethyl-2-nitro-2-hexene 30 3-Methyl-l-nitTO-l-butene 43 5-Ethyl-3-nitro-3-heptene 31 1-Nitro-l-hexene 44 3-Nitro-3-decane 32 2-Nitro-l-hexene 45 4-Ethyl-3-nitro-2-Octene 33 34