Purpose Theory Staff Site Universitas Negeri Yogyakarta Physc.Chem Lab W2
where the contact angle has been assumed to be 0
o
, gives a simple expression for the surface tension
γ = ½ r h ρ g ................ ......................................................................5 If we know the surface tension of the water against air, we can determine the surface
tension relative of others liquids such as methanol, ethanol, palm oil, etc. The surface tension of water is :
γ
a
= ½ r h
a
ρ
a
g ...............................................................................................6 and the surface tension of other liquid example X is
γ
x
= ½ r h
x
ρ
x
g...............................................................................................7 arrangement eq 6 and 7 gives an expression of the surface tension of x :
a a
a x
x x
h h
................................................................................................8