1. In one paragraph, define the Surface potential and the Zeta potential of a colloidal solution.
2. Provide typical values of the Hamaker constant for Au and SiO2 nanospheres immersed in water.
3. Find (or interpolate from a published table of values) the values for εr (the relative dielectric permittivity) of liquid H2O at 0, 25, 50 and 100 °C.