No return to zero of correction before the experiment; inaccurate reset or no reset
after a platinum plate or ring being hanged.
Sample contamination in wrong operation process
The characteristic of liquid to be tested is changing with time. The liquid should be
stirred evenly with the same ratio and in full rest.
The wetability of the liquid is not very high, it has viscosity or volatility.
4.2 Poor repeatability
Platinum plate or ring is not clean.
The characteristic of liquid to be tested is changing with time. The liquid should be
stirred evenly with the same ratio and in full rest.
4.3 Platinum ring / plate maintenance
To keep the experiment accuracy, please make sure platinum ring is standard round.
Please put deformed one back to the container and gently smooth it with tweezers. If the
ring is deformed badly or damaged, please buy a new one.
Check whether the platinum ring on the holder is parallel to the liquid level.
V.Appendix
5.1 Surface tension values of some liquid at 20
℃
Some of the liquid γ (20
℃
)
liquid
γ
（
mN/m
）
liquid-steam
water-liquid
water
72.75
octane
21.69
51.68
dodecane
25.44
52.90
hexane
27.46
53.77
benzene
28.88
35.0
tetrachloromethane
26.77
45.0
octanol
27.53
8.5
