How cold is ethanol-dry ice? - (Mar/16/2005 )

Some protocols recommend ethanol-dry ice (or ethanol added to frozen CO2) as an alternative to freezing in liquid nitrogen.

I wonder how cold is ethanol-dry ice?

Dry-ice on is -78.5°C. Liquid nitrogen is -196°C. Ethanol-dry ice is how much colder than -80°C?

from the isogeochem mailing list, posted by Dr. Haraldur R. Karlsson (google is your friend):

Some Useful Laboratory Cooling Mixtures

Mixture Mixture temperature (Centigrade)

p-Xylene/Liquid nitrogen 13
p-Dioxane/Liquid nitrogen 12
Cyclohexane/Liquid nitrogen 6
Benzene/Liquid nitrogen 5
Formamide/Liquid nitrogen 2
Aniline/Liquid nitrogen -6
Cycloheptane/Liquid nitrogen -12
Benzonitrile/Liquid nitrogen -13
Ethylene glycol/Dry ice -15
o-Dichlorobenzene/Liquid nitrogen -18
Tetrachloroetane/Liquid nitrogen -22
Carbon tetrachloride/Liquid nitrogen -23
Carbon tetrachloride/Dry ice -23
m-Dichlorobenzene/Liquid nitrogen -25
Nitromethane/Liquid nitrogen -29
o-Xylene/Liquid nitrogen -29
Bromobenzene/Liquid nitrogen -30
Iodobenzene/Liquid nitrogen -31
Thiophene/Liquid nitrogen -38
3-Heptanone/Dry ice -38
Acetonitrile/Liquid nitrogen -41
Pyridine/Liquid nitrogen -42
Acetonenitrile/Dry ice -42
Chlorobenzene/Liquid nitrogen -45
Cylcohexanone/Dry ice -46
m-Xylene/Liquid nitrogen -47
n-Butyl amine/Liquid nitrogen -50
Diethyl carbitol/Dry ice -52
n-Octane/Liquid nitrogen -56
Chloroform/Dry ice -61(-77)
Chloroform/Liquid nitrogen -63
Methyl iodide/Liquid nitrogen -66
Carbitol acetate/Dry ice -67
t-Butyl amine/Liquid nitrogen -68
Ethanol/Dry ice -72
Trichloroethylene/Liquid nitrogen -73
Butyl acetate/Liquid nitrogen -77
Acetone/Dry ice -78
Isopropanol/Dry ice -78
Isoamyl acetate/Liquid nitrogen -79
Acylonitrile/Liquid nitrogen -82
Sulfur dioxide/Dry ice -82
Ethyl acetate//Liquid nitrogen -84
Ethyl methyl ketone/Liquid nitrogen -86
Acrolein/Liquid nitrogen -88
Nitroethane/Liquid nitrogen -90
Heptane/Liquid nitrogen -91
Cyclopentane/Liquid nitrogen -93
Hexane/Liquid nitrogen -94
Toluene/Liquid nitrogen -95
Methanol/Liquid nitrogen -98
Diethyl ether/Dry ice -100
n-Propyl iodide/Liquid nitrogen -101
n-Butyl iodide/Liquid nitrogen -103
Cyclohexane/Liquid nitrogen -104
Isooctane/Liquid nitrogen -107
Ethyl iodide/Liquid nitrogen -109
Carbon disulfide/Liquid nitrogen -110
Butyl bromide/Liquid nitrogen -112
Ethyl bromide/Liquid nitrogen -119
Acetaldehyde/Liquid nitrogen -124
Methyl cyclohexane/Liquid nitrogen -126
n-Pentane/Liquid nitrogen -131
1,5-Hexadiene/Liquid nitrogen -141
Isopentane/Liquid nitrogen -160