chemistry

SURFACE CHEMISTRY

1. The isothermal variation of extent of adsorption with pressure is
   
   xm
    = K p^{1 / n}
   where x = mass of the adsorbed by the mass m of adsorbent at the pressure P,K and n are constant for a given pair of adsorbent and adsorbate.
2. Collidal Solution
   
   • True solution (size < 1nm)
   • Collidal Solution (size 1nm - 100nm)
   • Suspension (size > 100nm)
   Flocculation value ∝ 
   1coagulating power
   
3. Hardy Schulze Rule
   
   • The ion having opposite charge to sol particles cause coagulation .
   • Coagulation power of an electrolyte depends on the valency of ion i.e., greater the valency more is the coagulating power.
4. Gold Number
   The no. of milligarm of the protective collide required to just present the coagulation of 10mL of red gold sol when 1 mL of 10% solution of NaCl is added to it .
   
   Lower the value of gold number greater is the protective power .