Which gas will be adsorbed on a solid to greater extent.
A gas with high critical temperature has high vander waal force due to which they are more easily liquefiable & hence more easily adsorb as adsorption decreases their energy
Which of the following factors affects the adsorption of a gas on solid ?
Extent of adsorption increase with increase in critical temperature
The volume of gases NH3, CO2 and CH4 adsorbed by one gram of charcoal at 298 K are in
Extent of adsorption & intermoleculer force ∞ vander waal const. (a) NH3 > CO2 > CH4
The heat of physisorption lie in the range of
Which of the following is not a gel ?
Milk is emulsion
Which of the following is used to adsorb water
H2O + SiO2 → SiO2. xH2O
An emulsion is colloidal system of
Emulsion :- (ℓ + ℓ) dispersed phase & dispersion medium both are liquid
Which of the following is a lyophobic colloid ?
Gelation, starch & gum are organic in nature & hence lyophilic in nature but S8 is inorganic in nature & hence lyophobic in nature
The nature of bonding forces in adsorption
Vander waal force is responsible for adsorption.
The Tyndall effect associated with colloidal particles is due to
Tyndall effect is due to scattering of light
Which one of the following is not applicable to chemisorption ?
Chemisorption is irreversible in nature because in chemisorption there are strong covalent bond are formed which do not brake easily to separate the reactants because of this it has high heat of adsorption, takes place at high temperatures and forms monolayers.
In the colloidal state the particle size ranges
Colloidal range of particle is 1nm-1000 nm
colloids are heterogeneous in nature & hence consist of two phase.
Colloids can be purified by
Milk is an example of
Milk is emulsion (butter fat dispersed in water).
Colloidal particles in a sol. can be coagulated by
The correct answer is option D
Stability of the lyophobic sols is due to presence of charge on colloidal particles. If charge is removed, particles come together and settle down. Spontaneous destabilization of solution is ageing and destabilization of solution by artificial means is called coagulation.
Methods of coagulation are as follows:
3. Addition of electrolytes
4. Mixing two oppositely charged sols
Fog is a colloidal system of
Fog (liquid + gas) dispersed phase Dispersion medium.
Given below are a few electrolytes, indicates which one among them will bring about the coagulation of a gold sol. quickest and in the least of concentration ?
As per Hardy shulze rule coagulation power a +ve charge which is maximum in Al3+.
When a colloidal solution is observed under ultramicroscope, we can see
Ultra–microscope is based on tyndall effect which is based on scattering of light.
Colloidal solution are classified on the basis of
Molecular size for colloidal range in 1nm–1000 nm.
The minimum concentration of an electrolyte required to cause coagulation of a sol. is called
The electrical charge on a colloidal particle is indicated by
Due to charge on colloidal particle they move under the influence of electric field.
Smoke precipitator works on the principle of
Neutralization of charge on colloid as per hardy shulze rule.
Which one of following statement is not correct in respect of lyophilic sols ?
Lyophilic colloids do not move in presence of electric field due to uncharged nature.
As2S3 sol is
As2S3 colloid can be represented as As2S3 s2–
so it is negatively charged.
Crystalloids differ from colloids mainly in respect of
Crystalloid & colloids differes in particle size & due to smaller size of crystalloid.
At the critical micelle concentration (CMC) the surfacent molecules
Micelle is a associated form of colloid
Alums purify muddy water by
Alums due to the charged nature of colloidal particle & hence coagular impurities in muddy water as per shulze rule.
Solute dispersed in ethanol is called
Ethanol is alcohol to the colloidal system is called alcosols.
Which one of the following is lyophilic colloid ?
Colloidal sols formed by mixing substances in a suitable dispersion medium are called lyophilic sols. These are quite stable. They are also known as reversible sols because the dispersion medium can be separated from the colloid by means of physical methods like evaporation. For e.g. gum, gelatin, starch, rubber etc.