# Surface Chemistry Test 4

Total Questions:50 Total Time: 75 Min

Remaining:

## Questions 1 of 50

Question:When the temperature is lowered and pressure is raised, the adsorption of a gas on a solid

Decreases

Increases

Remains unaffected

Decreases first then increases

## Questions 2 of 50

Question:The charge on $$A{s_2}{S_3}$$ sol is due to the adsorbed

$${H^ + }$$

$$O{H^ - }$$

$${O^{2 - }}$$

$${S^{2 - }}$$

One

Two

Multi

Zero

## Questions 4 of 50

Question:The colloidal system consisting of a liquid adsorbent in a solid adsorbate is termed as

Aerosol

Sol

Foam

Gel

## Questions 5 of 50

Anhydrous calcium chloride

Ferric hydroxide

Conc. $${H_2}S{O_4}$$

Activated coconut charcol

## Questions 6 of 50

Question:The equation for Freundlich adsorption isotherm is

$$\frac{x}{m} = k{p^{1/n}}$$

$$x = mk{p^{1/n}}$$

$$x/m = k{p^{ - n}}$$

All of these

## Questions 7 of 50

Question:Enzymes with two sites are called

Apoenzyme

Holoenzyme

Allosteric enzyme

Conjugate enzyme

## Questions 8 of 50

Question:In a reversible reaction, a catalyst will affect the rate of

Forward reaction

Reverse reaction

Forward and reverse reaction

Neither nor

## Questions 9 of 50

Question:Which of the following statements is true for a catalyst

It increases the energy of the reactants

It decreases the energy of the products

It decreases the energy of the reactants

It does not change the enthalpy of the reactants

## Questions 10 of 50

Question:Which one of the following changes when catalyst is used in a reaction

Heat of reaction

Product of reaction

Equilibrium constant

Activation energy

## Questions 11 of 50

Question:Enzymes are

Micro-organisms

Proteins

Inorganic compounds

Moulds

## Questions 12 of 50

Question:A catalyst is a substance which

Increases the rate of a reaction

Increases the amount of the products formed in a reaction

Decreases the temperature required for the reaction

Alters the speed of the reaction remaining unchanged chemically at the end of the reaction

## Questions 13 of 50

Question:In a homogeneous catalysis

The catalyst and the reactants should be gases

The catalyst and the reactants should form a single phase

Catalyst and the reactants are all solids

The catalyst and the reactions are all liquids

## Questions 14 of 50

Question:Which requires catalyst

$$S + {O_2} \to S{O_2}$$

$$2S{O_2} + {O_2} \to 2S{O_3}$$

$$C + {O_2} \to C{O_2}$$

All

## Questions 15 of 50

Question:Gold number is

The number of mg of lyophilic colloid which should be added to 10 ml of ferric hydroxide sol so as to prevent its coagulation by the addition of 1 ml of 10% sodium chloride solution

The number of mg of lyophilic colloid which should be added to 10 ml of standard gold sol so as to prevent its coagulation by the addition of 1 ml of 10% $$NaCl$$

The mg of gold salt to be added to a lyophilic colloid to coagulate it

The mg of an electrolyte required to coagulate a colloid

## Questions 16 of 50

Question:Starch dispersed in hot water is an example of

Emulsion

Hydrophobic sol

Lyophilic sol

Associated colloid

## Questions 17 of 50

Question:Gold number is associated with

Only lyophobic colloids

Only lyophilic colloids

Both lyophobic and lyophilic colloids

None of these

## Questions 18 of 50

Question:The purification of the colloidal particles from crystalloid dimensions through semipermeable membrane is known as

Coagulation

Dialysis

Ultrafiltration

Peptisation

## Questions 19 of 50

Question:In emulsions, the dispersion medium and dispersed phase are

Both solids

Both gases

Both liquids

One is solid and other is liquid

## Questions 20 of 50

Question:Which one of the following is not a colloidal solution

Smoke

Ink

Air

Blood

## Questions 21 of 50

Question:Which is a natural colloidal

Sodium chloride

Urea

Canesugar

Blood

## Questions 22 of 50

Question:Brownian motion is due to

Temperature fluctuation within the liquid phase

Attraction and repulsion between charge on the colloidal

Impact of molecules of the dispersion medium on the colloidal particles

Convective currents

## Questions 23 of 50

Question:Milk can be preserved by adding a few drops of

Formic acid solution

Formaldehyde solution

Acetic acid solution

Acetaldehyde solution

## Questions 24 of 50

Question:Lyophobic colloids are

Reversible colloids

Irreversible colloids

Protective colloids

Gum proteins

## Questions 25 of 50

Question:Which of the following pairs of ions would be expected to form precipitate when their dilute solution are mixed

$$N{a^ + },\,SO_3^{2 - }$$

$$NH_4^ + ,\,CO_3^{2 - }$$

$$N{a^ + },\,{S^{ - 2}}$$

$$F{e^{ + 3}},\,PO_4^{ - 3}$$

## Questions 26 of 50

Question:Jelly is a form of

Suspension

Colloidal solution

Supersaturated solution

True solution

## Questions 27 of 50

Question:The reason for the stability of a lyophobic sol is

Brownian movement

Tyndall effect

Electric charge

Brownian movement and electric charge

## Questions 28 of 50

Question:Which one can act as semipermeable membrane

Phenol layer

$$C{a_3}{(P{O_4})_2}$$

$$C{u_2}Fe{(CN)_6}$$

All of these

## Questions 29 of 50

Question:In which particles can pass through semipermeable membrane

Molecules of solvent

Complex ions

Simple ions

Molecules of solute

## Questions 30 of 50

Question:When excess of electrolyte is added to a colloid it

Coagulates

Precipitates

Gets diluted

Does not change

## Questions 31 of 50

Question:Different colloidal particles of gold having different colours, obtained from different methods due to

Variable valency of gold

Different concentration of gold particles

Different types of impurities

## Questions 32 of 50

Question:Which one of the following is lyophilic colloid

Gelatin

Sulphur

Gold

Carbon

## Questions 33 of 50

Question:Which of the following represents surfactant molecule

$${C_{17}}{H_{36}}$$

$${C_{17}}{H_{25}}CO{O^ - }N{a^ + }$$

$${H_2}O$$

None of these

## Questions 34 of 50

Question:Emulsifiers are generally

Soap

Synthetic detergents

Lyophilic sols

All of these

## Questions 35 of 50

Question:In shaving cream, the dispersion medium is

Liquid

Gas

Solid

None of these

## Questions 36 of 50

Question:The example of heteropolar sol is

Starch sol in water

Rubber sol in water

Protein sol in water

Sulphur sol

## Questions 37 of 50

Question:Milk is an example of

Pure solution

Emulsion

Gel

Suspension

## Questions 38 of 50

Question:Dialysis is the process of separation of

Suspended particles from colloids

Suspended particles from crystalloids

Colloidal particles from crystalloids

Colloidal particles from gel

## Questions 39 of 50

Question:At the critical micelle concentration, the surfactant molecules

Decompose

Dissociate

Associate

Become completely soluble

## Questions 40 of 50

Question:The decomposition of $${H_2}{O_2}$$ can be slowed down by the addition of small amount of phosphoric acid which act as

Promoter

Inhibitor

Detainer

Stopper

## Questions 41 of 50

Question:A detergent is a

Cleaning agent

Drug

Catalyst

Vitamin

## Questions 42 of 50

Question:Blood may be purified by

Dialysis

Electro-osmosis

Coagulation

Filtration

## Questions 43 of 50

Question:The stability of lyophilic colloidal sol is due to

Both charge and salvation

Only salvation

Only charge

None of these

## Questions 44 of 50

Question:Which of the following statement is false

Every solid substance can be brought into colloidal state

Colloidal particles carry electrical charges

Every solid substance can be made to behave like a lyophilic colloid

Addition of electrolytes causes flocculation of colloidal particles

## Questions 45 of 50

Question:A colloidal system in which gas bubbles are dispersed in a liquid is known as

Foam

Sol

Aerosol

Emulsion

## Questions 46 of 50

Question:On adding few drops of dilute $$HCl$$ or $$FeC{l_3}$$ to freshly precipitated ferric hydroxide a red coloured colloidal solution is obtained. The phenomenon is known as

Peptisation

Dialysis

Protective action

Dissolution

## Questions 47 of 50

Question:Which of the following can act as protective colloids

Hydrophobic sols

Hydrophilic sol

Gold sol

None of these

## Questions 48 of 50

Question:A catalyst is a substance which

Is always in the same phase as in the reactions

Alters the equilibrium in a reaction

Does not participate in the reaction but alters the rate of reaction

Participates in the reaction and provide an easier pathway for the same

## Questions 49 of 50

Question:Cod liver oil is

An emulsion

Solution

Colloidal solution

Suspension

## Questions 50 of 50

Question:An aerosol is a