CORRELATION OF FIRE HAZARD CHARACTERISTICS WITH CHEMICAL STRUCTURE. XI. HALOALKANES

The correlation of chemical structure and fire-dangerous properties is studied in number of haloalkanes. The carbon rule well works for these compounds. The empirical equations of calculation are offered for boiling point (Tb (K) = 248,5 – 0,69NC 2 + 33,7NC, Tb (K) = 0,01 3 – 0,71 2 + 26,73 + 238, Tb (K) = 86,8 + 3,4Ñs + 535,5
Ñs 0 5, – 46,6
Ñs— for bromoalkanes; Tb (K) = 283,1 – 0,743NC 2 + 33NC, Tb (K) = 283,06 – 0,3303 2 + 21,969 , Tb (K) = 185,98 + 408,77
Ñs 0 5, — for iodoalkanes; Tb (K) = = 55,2NC – 1,45NC 2 + 368,44
NC 0 5, – 167
NC 2 – 60,56, Tb (K) = 75,28 + 98,36 0,5, Tb (K) = 65,93 + + 459,11
Ñs 0 5, — for fluoroalkanes); flash point (FP(K) = 211,4 – 0,57NC 2 + 21,7NC, FP(K) = –0,253 2+ + 14,5 + 211,4, FP (K) = 200 + 364,7
Ñs – 215,4
Ñs 2 + 51,4
Ñs 3 , FP (K) = 0,83Tb – 6,03NC + 5,12, FP (K) = 25,636Hv 0 69 , — for bromoalkanes; FP (K) = 262,7 – 17,93NC + 14,33NC 2 – 2,47NC 3 + + 0,183NC 4 – 0,005NC 5 , FP (K) = 211,17 – 23,6 + 0,007 3 + 66,4(ln ) 2 + (390,77 ln )
2 , FP (K) = = 27,3Ñs – 0,049Ñs 3 + (993,8lnÑs)
Ñs + 565,24
Ñs 2 – 194,3, FP (K) = 0,957Tb – 10,33NC – 37,95, FP (K) = 21,57Tb 0 5, – 128,39 — for iodoalkanes; FP (K) = 167,8 + 23,93NC 0 5, lnNC, FP (K) = = 158 + 17,51 0,5 ln , FP (K) = 154,24 + 262,16
Ñs, FP (K) = 0,21Tb + 12,89NC + 117,19, FP (K) = = 0,025Tb 1 5, + 98,16 — for fluoroalkanes); refractive index (nD = 1,428 – 0,0012NC + 0,014NC 0 5, – – 0,161
NC 1 5, + 0,154
NC 2 , nD = 1,499 – 0,0012 0,5 – 0,1699
0,5 + 0,08
, nD = 1,49 + 0,0005Ñs 1 5, – – 0,027Ñs 0 5, – 0,0004
Ñs 2 — for bromoalkanes; nD = 1,46 + 0,067
NC 0 5, , nD = 1,46 + 0,082
0,5, nD = (2,14 + 0,059Ñs 0 5, ) 0,5— for iodoalkanes; nD = 1,49 – 0,94
NC + 1,65
NC 2 – 1,04
NC 3 , nD = 1,68 – – 0,0004 1,5 – 1,04
0,5 + (1,85 ln )
2 , nD = 1,63 – 0,25Ñs + 0,126Ñs 1 5, – 0,019Ñs 2 – 0,06
Ñs — for fluoroalkanes); lower flammability limit (LFL (%) = 14,4 – 0,031NC 3 + 0,68NC 2 – 5,15NC) and heat of vaporization (Hv (kJ
mole) = 11,6 – 2,07NC + 0,345NC 1 5, + 13,8NC 0,5 — for bromoalkanes). For normal haloalkanes NÑ is number of carbon atoms, = 1,5NÑ; ÑS is the stoichiometric concentration. For isomeric compounds NÑ is the conventional carbon chain, -pseudo-factor: = NÑ + + (2NÑ +1 – Nhal)
4; ÑS is the pseudo-stoichiometric concentration. In the modified Ormandy– Craven's formula the values of coefficients a (–37,55) and b (0,538) are improved for bromoalkanes.