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The correct option among the following is :

  • Option 1)

    Colloidal medicines are more effective because they have small surface area.

  • Option 2)

    Addition of alum to water makes it unfit for drinking .

  • Option 3)

    Colloidal particles in lyophobic sols can be precipitated by electrophoresis.

  • Option 4)

     Brownian motion in colloidal solution is faster if the viscosity of the solution is very high.

    Properties of Colloidal Solutions - Coagulation or Precipitation - wherein The stability of the lyophobic sols is due to the presence of charge on colloidal particles. If somehow the charge is removed the particles will come nearer to each other and settle down under gravity.       Properties of Colloidal Solutions - Electrophoresis - wherein The existance of charge on colloidal...

Peptization is a :

  • Option 1)

    process of bringing colloidal molecule into solution

  • Option 2)

    process of converting soluble particles to form colloidal solution

  • Option 3)

    process of converting precipitate into colloidal solution

  • Option 4)

    process of converting a colloidal solution into precipitate 

  Preparation of Colloids - Peptization - wherein During peptization, the precipitate absorbs one of the ions of the electrolyte on its surface. This causes the development of positive or negative charge on precipitates, which ultimately break up into smaller particles of the size of a colloid.       Peptization is a process of converting precipitate into colloidal solution .  option (3) is...

The principle of column chromatography is:

  • Option 1)

    Gravitational force

  • Option 2)

    Capillary action

  • Option 3)

    Differential absorption of the substances on the solid phase.

  • Option 4)

    Differential adsorption of the substances on the solid phase.

The main principle involved in column chromatography is adsorption of the solutes of a solution through a stationary phase & separates the  mixture into individual components. This is based on the affinity towards the mobile phase & stationary phase. option (4) is correct. Option 1)Gravitational forceOption 2)Capillary actionOption 3)Differential absorption of the substances on the solid...

Among the following, the INCORRECT statement about colloids is:

 

  • Option 1)

    They can scatter light.

  • Option 2)

    They are larger than small molecules and have high molar mass.

  • Option 3)

    The osmotic pressure of a colloidal solution is of a higher order than the true solution at the same concentration.

  • Option 4)

    The range of diameters of colloidal particles is between 1 and 1000 nm.

  Colloids - A colloid is a heterogeneous system in which one substance is dispersed as very fine particles in another substance called disperson medium. - wherein The range of diameter is between 1 and 100 nm.     Multimolecular Colloids - On dissolution, a large number of atoms or smaller molecules of a substance aggregate together to form species having size in the colloidal range (less...

A gas undergoes physical adsorption on a surface and follows the given Freundlich

adsorption isotherm equation

\frac{x}{m}=kp^{0.5}

Adsorption of the gas increases with: 

  • Option 1)

    Decrease in p and increase in T

  • Option 2)

    Decrease in p and decrease in T

  • Option 3)

    Increase in p and decrease in T

  • Option 4)

    Increase in p and increase in T

Freundlich adsorption isotherm equation:  Adsorption capacity  increases with increase in Pressure. Now; Physisorption ( Physical adsorption ) is always an exothermic process.  Adsorption decreases with increase in temperature.  option (3) is correct.Option 1)Decrease in p and increase in TOption 2)Decrease in p and decrease in TOption 3)Increase in p and decrease in TOption 4)Increase in p...

Adsorption of a gas follows Freundlich adsorption isotherm. x is the mass of the gas adsorbed on mass m of the adsorbent. The plot of \log\frac{x}{m} versus \log P is shown in the given graph. \frac{x}{m} is proportional to :


 

  • Option 1)

    P^{2/3}

  • Option 2)

    P^{3}

  • Option 3)

    P^{2}

     

  • Option 4)

    P^{3/2}

 
Option 1) Option 2) Option 3)   Option 4)

 The reason for “drug induced poisoning” is :

  • Option 1)

     Binding reversibly at the active site of the enzyme

  • Option 2)

    Bringing conformational change in the binding site of enzyme

  • Option 3)

     Binding irreversibly to the active site of the enzyme

  • Option 4)

    Binding at the allosteric sites of the enzyme

     

 
Option 1)  Binding reversibly at the active site of the enzyme Option 2) Bringing conformational change in the binding site of enzyme Option 3)  Binding irreversibly to the active site of the enzyme Option 4) Binding at the allosteric sites of the enzyme  

An example of solid sol is :

  • Option 1)

    Paint .

  • Option 2)

    Gem stones.

  • Option 3)

     Butter.

  • Option 4)

    Hair cream .

  Fog/ Mist - When a large mass of air containing dust particle is cooled below its dew point, the moisture from the air condenses on the surface of these particles forming fine droplets. These droplets being colloidal in nature continue to float in air in the form of fog or mist. - As we know that Gem stones are the the example of solid sol.    Option 1)Paint .Option 2)Gem stones.Option...

The correct match between Item I and Item II is :

       Item I                              Item II 

(A) Allosteric  effect             (P) Molecule binding to the active site of enzyme 

(B) Competitive inhibitor     (Q) Molecule crucial for communication in the body 

(c) Receptor                        (R)  Molecule binding to a site other than the active site of enzyme

(D) Poison                          (S) Molecule binding to the enzyme covalently

 

  • Option 1)

    (A) \rightarrow (P) ; (B) \rightarrow (R) ; (C) \rightarrow (Q); (D) \rightarrow (S) 

  • Option 2)

    (A) \rightarrow (R) ; (B) \rightarrow (P) ; (C) \rightarrow (S); (D) \rightarrow (Q) 

  • Option 3)

    (A) \rightarrow (R) ; (B) \rightarrow (P) ; (C) \rightarrow (Q); (D) \rightarrow (S) 

  • Option 4)

    (A) \rightarrow (P) ; (B) \rightarrow (R) ; (C) \rightarrow (S); (D) \rightarrow (Q) 

  Enzyme Catalysis - Numerous reaction that occurs in the bodies of animals and pants to maintain the life process is catalyzed by enzymes. They are called biochemical catalysts. - wherein NCERT (based on concept) A-R; B-P; C-Q; D-SOption 1)(A)  (P) ; (B)  (R) ; (C)  (Q); (D)  (S) Option 2)(A)  (R) ; (B)  (P) ; (C)  (S); (D)  (Q) Option 3)(A)  (R) ; (B)  (P) ; (C)  (Q); (D)  (S) Option...

Among the following, the false statement is :

  • Option 1)

    Tyndall effect can be used to distinguish between a colloidal solution and a true solution :

  • Option 2)

    Latex is a colloidal solution of rubber particles which are positively charged 

  • Option 3)

    It is possible to cause artificial rain by throwing electrified sand carrying charge opposite to the one on clouds from an aeroplane. 

  • Option 4)

    Lyophilic sol can be caogulated by adding an electrolyte.

  The reason for the Tyndall Effect - The Tyndall effect is due to the fact that colloidal particles scatter light in all directions in space. This scattering of light illuminates the path of the beam in the colloidal dispersion. The bright cone of the light is called Tyndall cone. -     Lyophilic Colloids - The word 'lyophilic' means liquid loving. colloidal sols directly formed by mixing...

Which of the following is not an example of heterogeneous catalytic reaction ?

  • Option 1)

    Ostwald's process

     

  • Option 2)

    Combustion of coal

  • Option 3)

    Hydrogenatoin of vegetable oils

  • Option 4)

    Haber's process

  Heterogeneous Catalysis - The catalytic process in which the reactants and the catalyst are in different phases is known as heterogeneous catalysis - wherein E.g.   As we have learned in combustion we do not require any catalyst forf the combustion of coal.  Option 1)Ostwald's process  Option 2)Combustion of coalOption 3)Hydrogenatoin of vegetable oilsOption 4)Haber's process

Wilkinson catalyst is :

  • Option 1)

    \left [ \left ( Ph_{3}P \right )_3IrCl \right ]

  • Option 2)

    \left [ \left ( Et_{3}P \right )_{3}RhCl \right ]

  • Option 3)

    \left [ \left ( Ph_{3}P \right )_{3}RhCl \right ]\: \: \: \: \: \: \: \left ( Et=C_{2} \right H_{5})

  • Option 4)

    \left [ \left ( Et_{3}P \right )_{3}IrCl \right ]

  Catalyst - A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the reaction. - wherein Berzelius in 1835, suggested the term catalyst for such substances.   Wilkinison catalyst is: Option 1)Option 2)Option 3)Option 4)

Hemoglobin  and gold sol are example of:

  • Option 1)

    Positively charged sols

  • Option 2)

    Negatively charged sols

  • Option 3)

    Positively and negatively charged sol respectively

  • Option 4)

    Negatively and positively charged sols,respectively

  Multimolecular Colloids - On dissolution, a large number of atoms or smaller molecules of a substance aggregate together to form species having size in the colloidal range (less than 1 nm). The species thus formed are called multimolecular colloids. E.g. Gold sol, sulphur sol. -    Option 1)Positively charged solsOption 2)Negatively charged solsOption 3)Positively and negatively charged sol...

Given 

Gas\; \; \; \; \; \; \; \; \; \; \; \; H_{2}\; \; \; CH_{4}\; \; \; CO_{2}\; \; \; SO_{2}

Critical\; \; \; \; \; \; \; \; \; 33\; \; \; 190\; \; \; 304\; \; \; 630

Temperature/K

On the basis of data given above predict which of the following gases shows least  adsorption on a definite amount of charcoal ?

  • Option 1)

    CH_{4}

  • Option 2)

    H_{2}

  • Option 3)

    SO_{2}

  • Option 4)

    CO_{2}

 

Physical Adsorption -

If the accumulation of gas on the surface of a solid occurs on account of weak van der Walls forces, the adsorption is termed as physical adsorption or physisorption.

-

 

 adsorption directly proportional to critical temperature.

As we have learned in the gaseous state the smaller the value of the critical temperature of the gas, lesser is the amount of adsorption.

so least adsorbed gas is H2 at its LT is 33K


Option 1)

CH_{4}

Option 2)

H_{2}

Option 3)

SO_{2}

Option 4)

CO_{2}

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The correct match between Item I and Item II is:

               Item I                                           Item II

(A)  Benzaldehyde                               (P) Mobile phase 

(B) Alumina                                          (Q) Adsorbant 

(C) Acetonitrile                                      (R) Adsorbate

  • Option 1)

    (A)\rightarrow (Q);(B)\rightarrow (P);(C)\rightarrow R

     

  • Option 2)

    (A)\rightarrow (Q);(B)\rightarrow (R);(C)\rightarrow (P)

  • Option 3)

    (A)\rightarrow (P);(B)\rightarrow (R);(C)\rightarrow (Q)

  • Option 4)

    (A)\rightarrow (R);(B)\rightarrow (Q);(C)\rightarrow (P)

  Adsorbate and Adsorbent - The molecular species or substance, which concentrates or accumulates at the surface is termed adsorbate and the material on the surface of which adsorption takes place is called adsorbent. - Benzaldehyde is adsorbate. Alumina behave as adsorbent. Acetonitrite work as mobile phase.  Option 1)  Option 2)Option 3)Option 4)

A dsorption of gas follows Freundlich adsorbtin isotherm. In the given plox ,x is the mass of the gas  adsorbent at pressure P.   \frac{x}{m}  is propotional to:

 

 

  • Option 1)

    p^{2}

  • Option 2)

    p^{\frac{1}{4}}

  • Option 3)

    p^{\frac{1}{2}}

  • Option 4)

    p

  Freundlich adsorption isotherm - Freundlich gave an empirical relationship between the quantity of gas adsorbed by a unit mass of solid adsorbent and pressure at a particular temperature - wherein (n>1) As we know that: From the graph     Logarithmic graph of Freundlich isotherm - - wherein The slope of the straight line gives the value of 1/n. The intercept on y-axis gives the value...
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