Surface Chemistry Flashcards
2KClO3——– 2KCl + 3O2 catalyst used
MnO2
2SO2 (g) ——–2 SO3 (g)
platinum
catalyst used in ostwald’s process
platinum gauze
CO+3H2 ——– product formed when Ni is used as catalyst
methane CH4
CO + 2 H2 ———- CH3OH catalyst used is
Cu/ZnO- Cr2O7
CO+H2 ——– Formaldehyde (HCHO) catalyst used
copper
Zeolites catalyst is made up
Aluminumsilicates
zeolite used in peroleum industry
ZSM-5
C12H22O11 + H2O ———— Glucose +Fructose enzyme used
invertase
C6H12O6 ———– C2H5OH enzyme involved is
Zymase
Starch ——— Maltose enzyme used
Diastase
contact process for manufacture of sulfuric acid the catalyst used is
platinum or V2O5
paints and cell fluids are ———– colloid
solid liquid
cheese butter is ———– colloid
Liquid solid (dispersed phase and dispersion medium) called as gel
Milk and hair cream is —————-colloid
Emulsion (liquid liquid)
Smoke is Solid in gas colloid where as Fog mist and insecticide spray is
Liquid in gas
pumice stone and foam rubber is ———– colloid
gas in solid (solid sol)
froth, soap, whipped cream are —————— colloids
Gas in liquid (foam)
colloids with alcohol as dispersion medium are called
Alcosol
lyophilic sols do not undergo coagulation true or false
true
size of multimolecular colloids is
less than 1nm
Few stong electrolytes form colloids above a particular concentration called as
critical micelle concentration (CMC)
micelle formation takes place above particular temperature called as
Kraft temperature
CMC of soap is
10-4 to 10-5 mol L-1
As2O3 on reaction with H2S gives a colloid whose formula is
As2S3
H2S gets oxidised by SO2 to form a substance which forms colloid in water. the substance is
sulfur
AuCl3 is reduced by formaldehyde (HCHO) to form a colloid in water
the reaction is
AuCl3 +HCHO+H2O———- Au+HCOOH+HCl
FeCl3 is hydrolysed to ———— which form a colloid
Fe(OH)3
Colloidal sols of Au, Ag and Pt are generally prepared by
Electrical disintegration or Bredig’s Arc method
precipitate is converted to colloidal sol by
peptisation (by using peptizing agent)
Colloidal solutions are stabilized by small amounts of ——–
electrolytes
Pore size of filter paper can be reduced by use of—————–
Colloidon solution eg 4% solution of nitro cellulose in mixture of alcohol and ether.
ultramicroscope works on principle of ——————
tyndall effect
Mixture milk and water appears blue when viewed by———– and red when viewed by ——————
reflected light
transmitted light
Haemoglobin sol carries ————- electrical charge
positive
Sols of metallic oxides carry ——-charge where as metallic sulfides carry ——– charge
positive
negetive
Sols of starch, gum gelatin, clay and charcoal carry ——-charge
negetive
metals sols carry ———– charge
negetive
basic dye stuffs like methylene blue sols carry———— charge whereas acidic dye stuffs eg eosin, congo red sols carry ——–charge
positive
negetive
Addition of AgNO3 solution to KI solution what is the resulting colloid
AgI/I- negetively charged colloid due to adsorption of I- from dispersion medium
Colloidal Sol formed when KI solution is added to AgNO3 solution is
AgI/Ag+ positively charged due to adsorption of Ag+ from dispersion medium
FeCl3 added to excess hot water SOl formed is
Fe2O3 xH2O/Fe3+ positively charged Sol
FeCl3 added to NaOH sol formed is
Fe2O3.xH2O/OH- negatively charged sol
colloids form two layers of opposites charges known as ———–
Helmholtz electrical double layer
Potential difference due to Helmholtz electrical double layer is called
Zeta potential or electrokinetic potential
movement of colloid particles under applied electric potential is called
electrophoresis
prevention of movement of particles during electrophoresis leads to
electroosmosis movement of dispersion medium
boiling of colloidal sol leads to
coagulation
increasing order of power of coagulation of negative sol by Al3+, Ba2+and Na+
Al3+>Ba2+>Na+ flocculatiing power increases with charge
minimum concntration of electrolyte in Millimoles per lit to cause precipitation of sol in two hours is called
Coagulating value
coagulating value is lowest for PO4 3-, Cl-, SO4 2-
PO43- as charge is highest
factors responsible for stability of lyophillic sols
charge and solvation
