Table of Surface-Tension at 20° C. (Quincke).

Liquid. Specific
Gravity.
Tension of surface
separating the liquid from
Angle of contact with
glass in presence of
Air. Water. Mercury. Air. Water. Mercury.
Water  1  81 · · 418 25° 32′ · · 25° 6′
Mercury 13.5432 540 418 · · 51° 8′ 26° 8′ · ·
Bisulfuride of Carbon  1.2687  32.1  41.75 372.5 32° 16′ 15° 8′ · ·
Chloroform  1.4878  30.6  29.5 399 · · · · · ·
Alcohol  0.7906  25.5 · · 399 25° 12′ · · · ·
Olive Oil  0.9136  36.9  20.56 335 21° 50′ 17° 47° 2′
Turpentine  0.8867  29.7  11.55 250.5 37° 44′ 37° 44′ 47° 2′
Petroleum  0.7977  31.7  27.8 284 36° 20′ 42° 46′ · ·
Hydrochloric Acid  1.1  70.1 · · 377 · · 42° 46′ · ·
Solution of Hyposulphite of Soda  1.1248  77.5 · · 442.5 23° 20′ · · 10° 42′
Olive Oil and Alcohol, 12.2.
Olive oil and aqueous alcohol (sp. g. .9231, tension of free surface25.5), 6.8, angle 87° 48′.

Quincke has determined the surface-tension of a great many substances near their point of fusion or solidification. His method was that of observing the form of a large drop standing on a plane surface. If K is the height of the flat surface of the drop, and k that of the point where its tangent plane is vertical, then

T = ½(K − k)²gρ

Quincke finds that for several series of substances the surface-tension is nearly proportional to the density, so that if we call (K - k)² = 2T/gρ the specific cohesion, we may state the general results of his experiments as follows:—

Surface-Tensions of Liquids at their Point of Solidification. From Quincke.

Substance.Temperature of
Solidification.
Surface-
Tension.
Platinum2000° C.1658
Gold1200°  983
Zinc360°  860
Tin230°  587
Mercury−40°  577
Lead330°  448
Silver1000°  419
Bismuth265°  382
Potassium58°  364
Sodium90°  253
Antimony432°  244
Borax1000°  212
Carbonate of Soda1000°  206
Chloride of Sodium· · 114
Water0°  86.2
Selenium217°  70.4
Sulphur111°  41.3
Phosphorus43°  41.1
Wax68°  33.4

The bromides and iodides have a specific cohesion about half that of mercury. The nitrates, chlorides, sugars and fats, as also the metals lead, bismuth and antimony, have a specific cohesion nearly equal to that of mercury. Water, the carbonates and sulphates, and probably phosphates, and the metals platinum, gold, silver, cadmium, tin and copper have a specific cohesion double that of mercury. Zinc, iron and palladium, three times that of mercury, and sodium, six times that of mercury.

Relation of Surface-tension to Temperature