3. Mono-polar surface and monopolar liquid , i.e.

Usually only electron donor polarity is observed.

This is similar to the case where there was an apolar liquid on a surface. This is because for AB interactions to have any significance, both the conjugate interactions should be present.

Some numbers have been presented below for better understanding.

1. Monopolar surfaces ( )

          Table 4.1:

Gelatin, PMMA, PVA, dextran, PEG, serum, albumin, and agarose are some other examples of important monopolar liquids.

2. Apolar and liquids having both electron donor and acceptor capabilities

Table 4.2:

Note: It might appear that glycerol is monopolar with electron donor capability as is quite high for it. But it is not so, because the product  is comparable to  in magnitude.