Download App

Surface Chemistry — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistrySurface Chemistry3 Marks
Question
Write one difference in each of the following:
  1. Multimolecular colloid and Associated colloid.
  2. Coagulation and Peptization.
  3. Homogeneous catalysis and Heterogeneous catalysis.
✓

Answer

  1.  
Multimolecular colloid Associated colloid
Aggregation of large number of small atoms or molecules. Aggregation of large number of ions in concentrated solutions.
  1.  
Coagulation Peptization
Settling down of colloidal particles. Conversion of precipitate into colloidal sol by adding small amount of electrolyte.
  1.  
Homogenous catalysis Heterogeneous catalysis
Reactants and catalyst are in same phase. Reactants and catalyst are in different phases.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Surface Chemistry→Surface Chemistry — all question types→Chemistry STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Iron has a body centred cubic unit cell with a cell edge of 286.65 pm. The density of iron is $7.87\ g\ cm^{–3}.$ Use this information to calculate Avogadro’s number $($At mass of $Fe = 56\ g\ mol^{–1}).$
→
What happens when
  1. Ethyl chloride is treated with NaI in the presence of acetone,
  2. Chlorobenzene is treated with Na metal in the presence of dry ether,
  3. Methyl chloride is treated with $KNO_2$?
Write chemical equations in support of your answer.
→
$[Ti(H_2O)]^{3+}$ is coloured while $[Sc(H_2O)_6]^{3+}$ is colourless.
→
Write the structure of the product when chlorobenzene is treated with methyl chloride in the presence of sodium metal and dry ether.
→
For the reaction $R\rightarrow P,$ the concentration of a reactant changes from $0.03 M$ to $0.02 M$ in $25$ minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
→
Give the structures of A and B in the following sequence of reactions:
  1. $\text{CH}_3\text{COOH}\xrightarrow[\Delta]{\text{NH}_3\ \ \ }\text{A}\ \ \ \xrightarrow{\text{NaOBr}}\text{B}$
  2. $\text{C}_6\text{H}_5\text{No}_2\xrightarrow{\text{Fe}/ \text{ HCl}}\text{A}\ \ \ \ \ \xrightarrow[0^\circ-5^\circ\text{C}]{\text{NaNo}_2+\text{HCl}}\text{B}$
  3. $\text{C}_6\text{H}_5\text{N}_2^+\text{Cl}^{-}\xrightarrow[\Delta]{\text{CuCN}}\text{A}\ \ \ \ \xrightarrow{\text{H}_2\text{O}/\text{ H}^+}\text{B}$
→
Calculate the charge of one mole of electrons.
→
Give reason:
(i) Transition elements exhibit higher enthalpies of atomisation.
(ii) In aqueous solution, $Cr ^{2+}$ is stronger reducting agent than $Fe ^{2+}$.
(iii) The second ionisation enthalpy of Cu is higher then $Z n$.
→
What are micelles? How do they differ from ordinary colloidal particles? Give two examples of micelle forming substances.
→
How would you differentiate between $S_N1$ and $S_N2$ mechanisms of substitution reactions? Give one example of each.
→