CBSE Questions for Class 12 Engineering Chemistry Surface Chemistry Quiz 6 - MCQExams.com

Physisorption is non-specific.
  • True
  • False
The substance on whose surface adsorption takes place is called an _______ .
  • absorbent
  • absorbate
  • solute
  • solvent
The catalyst in photosynthesis is:
  • sunlight
  • water
  • chlorophyll
  • CO2CO2
Cleansing action of soaps includes:
  • formation of micelles
  • emulsification of oil or grease
  • lowering of surface tension of water
  • all of the above
Which metal is used as a catalyst in the hydrogenation of oils?
  • Iron
  • Sodium
  • Nickel
  • Gold
The colloidal dispersion of a liquid in a liquid is called:
  • mixture
  • emulsion
  • precipite
  • none of these
Whenever a mixture of gases is allowed to come in contact with a particular adsorbent under the same conditions, the more strong adsorbate is adsorbed to greater extent irrespective of its amount present. For example, H2OH2O is adsorbed to more extent on silica gel than N2N2 and O2O2. This shows that some adsorbates are preferentially adsorbed. It is also observed that preferentially adsorbable adsorbents can displace a weakly adsorbed substance from the surface of an adsorbent.

Which of the gas can displace remaining all the gases?
  • O2O2
  • N2N2
  • COCO
  • H2H2
When KClO3KClO3 is heated, it decomposes into KClKCl and O2O2. If some MnO2MnO2 is added, the reaction goes much faster because :
  • MnO2MnO2 decomposes to give O2O2
  • MnO2MnO2 provides heat by reacting
  • Better contact is provided by MnO2MnO2
  • MnO2MnO2 acts as a catalyst.
Activated charcoal is used to remove colouring matter from pure substances. It works by:
  • oxidation
  • reduction
  • bleaching
  • adsorption
In physical adsorption, the adsorbent and adsorbate are held together by the:
  • Ionic force
  • Covalent force
  • Van der Waal's force
  • H-bonding
The action of cleaning of oily dirt by soap is based on
  • Solubility in water
  • Hydrophilic property
  • Hydrophobic property
  • Presence of both hydrophilic and hydrophobic groups
Rate of physical adsorption increases with:
  • decrease in surface area
  • decrease in temperature
  • decrease in pressure
  • All of the above 
Cow milk, an example of natural emulsion is stabilised by:
  • Fat
  • Water
  • Casein
  • Mg2+2+ ions

The metal used as a catalyst in the hydrogenation of oil is:

  • sodium
  • nickel
  • mercury
  • manganese

A substance which alters the rate of reaction:

  • reactant
  • product
  • ingredient
  • catalyst
If the adsorbate is held on the surface of an adsorbent by force of van der Waals type, the adsorption is called:
  • van der Waals adsorption
  • physical adsorption
  • physisorption
  • All of these
The cleaning action of a soap is due to soap lather, which reduced the interfacial tension and solubilises the oily dirt into the water by emulsification.
  • True
  • False

Which metal is used as a catalyst in the hydrogenation of oils?

  • Iron
  • Sodium
  • Nickel
  • Gold
Adsorption increases with increase in temperature in Physisorption.
  • True
  • False
Which of the following is/are true for physisorption?
  • Easily liquefied gases are more adsorbed.
  • Weak van der Waals forces cause the adsorption process.
  • Only unimolecular layer formation.
  • Adsorbtion increases with rise in temperature.
Weak van der Waal forces are responsible for Physisorption.
  • True
  • False
Toothpaste and mud are examples of :
  • foam and sol respectively
  • sol
  • gel and emulsion respectively
  • foam
The physical adsorption of gases on the solid surface is due to:
  • covalent bond
  • hydrogen bond
  • ionic bond
  • van der wal's force
Match the columns.
I)Dusta)Gel
II)Milkb)Emulsion
III)Toothpastec)Solid aerosol
IV)Opald)Sol
  • I-d, II-a, III-c, IV-b
  • I-c, II-b, III-d, IV-a
  • I-b, II-c, III-a, IV-d
  • I-a, II-d, III-b, IV-c
The catalyst used in preparation of oxygen from hydrogen peroxide is:
  • manganese dioxide
  • magnesium oxide
  • manganese oxide
  • manganese sulphate
Which of the following rules states that with the increase of every 10C10C temperature the rate of metabolic activity gets doubled?
  • Van't Hoff's rule
  • Bergman's rule
  • Allen's rule
  • Jordon's rule
Animal charcoal is used in decolorising colour of liquids because it is a good :
  • adsorbate
  • adsorbent
  • oxidising agent
  • reducing agent
Peptization denotes:
  • hydrolysis of proteins
  • digestion of food
  • breaking and dispersion into colloidal state
  • precipitation of solid from colloidal dispersion
The change in energy for the overall reaction is defined by letter :

482808_907122e5e2e243198d38ab8827ec1725.png
  • A
  • B
  • C
  • Y
  • X
Find the false statement for chemical catalysts ?
  • They are not consumed during the chemical reaction
  • They cannot make nonspontaneous reactions occur
  • They do not have to be the same phase as the reactant molecules
  • They shift equilibrated reactions to the product's side
  • Enzymes are biological catalysts
Statement I: Above reaction is exothermic.
Because
Statement II: Energy difference B is greater than energy difference A.
482811_0af1721cea87400c849ba143cbfd753d.png
  • true, true, correct explanation
  • true, true, not correct explanation
  • true, false
  • false, true
  • false, false
When two immiscible liquids are shaken together vigorously, it may form :
  • a solution
  • a tincture
  • a sediment
  • a hydrated solution
  • a colloidal dispersion
Recorded data: 
Before:: CuO+CuO+porcelain boat=62.869=62.869g
CaCl2+CaCl2+U-tube=80.483=80.483g
After:Porcelain boat++contents =54.869=54.869g
CaCl2+CaCl2+U-tube=89.483=89.483g
Reactions:Zn(s)+2HCl(aq)ZnCl2(aq)+H2(g)Zn(s)+2HCl(aq)ZnCl2(aq)+H2(g) then H2(g)+CuO(s)H2O(g)+Cu(s)H2(g)+CuO(s)H2O(g)+Cu(s)
What was the reason placing tube of CaCl2CaCl2 between the generator and the tube containing the porcelain boat?
481531_730dcdd5d23a4e57bbd7d7364ac8e4f7.png
  • To absorb evaporated HCl
  • To absorb evaporated H2OH2O
  • To slow down the gases released
  • To absorb the evaporated Zn particles
  • To remove the initial air that passes through the tube
Peptisation is a process in which:
  • precipitation becomes true solution
  • true solution becomes a suspension
  • a colloid gets coagulation
  • a suspension gets converted into a colloid
An uncatalyzed reaction' s progress diagram is shown by solid line. Which of two dotted lines represents the same reaction in the presence of catalyst?
481088.JPG
  • A
  • B
  • C
  • D
  • E

Activation energy of the reaction is corresponded by letter :

482807_9e020bc250254577a2b8bc6b7fdce720.png
  • A
  • B
  • C
  • Y
  • X
After observing the graph, which statement tells that the chemical reaction is exothermic?
481720_a5ed29a6632747268ea284efb4613eca.png
  • The potential energy at point 2
  • The energy difference between points 1 and 2
  • The time elapsed between points 2 and 3
  • The energy difference between points 1 and 3
  • The time needed to reach point 3
A catalyzed reaction mechanism has a ____ activation energy and thus, causes a _____ reaction rate.
  • higher, lower
  • higher, higher
  • lower, higher
  • lower, steady
  • higher, steady
Delta formation at the mouth of river takes place by:
  • coagulation of negative salt ions and positive river particles
  • coagulation of positive salt ions and negative river particles
  • coagulation of positive salt ions and positive river particles
  • coagulation of negative salt ions and negative river particles
A catalyst :
  • Changes ΔGΔG for an equation
  • Acts by increasing the rate of the forward reaction more than the reverse reaction
  • Raises the equilibrium constant of a system
  • May have molecular weight as low as 1 or higher than 200,000
  • Does not react chemically during the course of a reaction
Which of the following pairs of colloidal solutions have dispersed phase as liquid and dispersed medium as gas?
  • Fog, mist
  • Butter, milk
  • Fog, smoke
  • Smoke, foam
What is a sol?
  • A solid dispersed in a liquid
  • A liquid dispersed in a gas
  • A gas dispersed in a liquid
  • A gas dispersed in a solid
Increased with the addition of a catalyst :
  • Standard voltaic potential
  • Entropy
  • Enthalpy
  • Reaction rate
  • Gibbs free energy
Catalyst used in Rosenmund reaction is:
  • SnSn
  • Zn/HClZn/HCl
  • Pd/BaSO4Pd/BaSO4
  • NiNi
To which of the following category does ice-cream belong?
  • Solution
  • Emulsion
  • Element
  • Suspension
Which letter corresponds to the activation energy in this reaction without the addition of a catalyst?
524577.jpg
  • A
  • B
  • C
  • D
  • E
The process of separating of cream from milk is called :
  • Emulsification
  • Demulsification
  • Emulsions
  • Electro-osmosis
Which one of the following systems has the smallest sized domains in its dispersed phase?
  • Nanoemulsion
  • Coarse suspension
  • Coarse emulsion
  • Microemulsion
Milk is an example of :
  • Suspension
  • True solution
  • Emulsion
  • None of the above
An example of a colloid which is an emulsion is :
  • Wipped cream
  • Mayonnaise
  • Fog
  • Gelatin
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