Surface chemistry practice · Mixed difficulty

An emulsifier is a substance which

Decomposition of urea into $\mathrm{N}{\mathrm{H}_3}\;\mathrm{and}\;\mathrm{C}{\mathrm{O}_2}$ is followed by the action of enzyme :

Which of the following statement is not correct for the catalyst?

For which colloidal substance the dispersed phase and dispersion medium are liquid and solid respectively?

Select the correct statements among the following

a) Foam is a colloidal solution of gas in liquid

b) Aerosol is a colloidal solution of liquid in gas

c) Gel is a colloidal solution of solid in liquid

d) Emulsion is a colloidal solution of liquid in liquid

Which forms micelles in aqueous solution above certain concentration?

In autocatalysis

The cotterells precipitator is used to :

The coagulation of $400 \mathrm{~mL}$ of a positive colloid took place when $1.46 \mathrm{~g}$ of $\mathrm{HCl}$ was added to it without changing the volume much. What is the flocculation value of $\mathrm{HCl}$ for the colloid?

$10 \%$ sites of catalyst bed have adsorbed by $\mathrm{H}_2$. On heating $\mathrm{H}_2$ gas is evolved from sites and collected at $0.03 \mathrm{~atm}$ and $300 \mathrm{~K}$ in a small vessel of $2.46 \mathrm{~cm}^3$.
No. of sites available is $5.4 \times 10^{16}$ per $\mathrm{cm}^2$ and surface area is $1000 \mathrm{~cm}^2$. Find out the no. of surface sites occupied per molecule of $\mathrm{H}_2$. $\left(\right.$ Given $\mathrm{N}_{\mathrm{A}}=6 \times 10^{23}$ )

In petrochemical industries, alcohols are directly converted to gasoline by passing over heated

Which of the following is an anionic detergent?

Bredig’s arc method cannot be used for the preparation of colloidal sol of

Which of the following is not a characteristic of chemisorption?

A sample of $16 \mathrm{~g}$ charcoal was brought into contact with $\mathrm{CH}_4$ gas contained in a vessel of 1 litre at $27^{\circ} \mathrm{C}$. The pressure of gas was found to fall from 760 to 608 torr. The density of charcoal sample is $1.6 \mathrm{~g} / \mathrm{cm}^3$. What is the volume of the $\mathrm{CH}_4$ gas adsorbed per gram of the adsorbent at 608 torr and $27^{\circ} \mathrm{C}$ ?

Which among the following is used to purify colloidal solution?

3 g of activated charcoal was added to 50 mL of acetic acid solution (0.06 N) in a flask. After an hour it was filtered and the strength of the filtrate was found to be 0.042 N. The amount of acetic acid adsorbed (per gram of charcoal) is

Assertion : Physical absorption of molecules takes place on surface only.

Reason : In this process, the bonds of the absorbed molecules are broken.

Which might have lowest value of critical micelle concentration in water

Which of the following is not a characteristic of physisorption of a gas on solid surface?

In an experiment, $200 \mathrm{~mL}$ of $0.5 \mathrm{M}$ oxalic acid is shaken with $10 \mathrm{~g}$ of activated charcoal and filtered. The concentration of the filtrate is reduced to $0.4 \mathrm{M}$. The amount of adsorption $\left(\frac{x}{m}\right)$ is

Isoelectric point is the pH at which colloidal particles

Addition of $\mathrm{FeC}{\mathrm{l}_3}$ to ${\mathrm{K}_4}\left[ {\mathrm{Fe}{{\left( {\mathrm{CN}} \right)}_6}} \right]$ in dilute and cold solution gives :

Which of the following is not a characteristic off chemical adsorption of a gas on solid surface ?

In an adsorption experiment, a graph between $\log (\mathrm{x} / \mathrm{m})$ versus $\log \mathrm{P}$ was found to be linear with a slope of $45^{\circ}$. The intercept on the $y$ axis was found to be 0.301 . The amount of the gas adsorbed per gram of charcoal under a pressure of $3.0 \mathrm{~atm}$ is

Which equation represents Freundlich adsorption isotherm (physical adsorption is basis of this theory)?

Which can adsorb larger volume of hydrogen gas?

Clouds, mist, fog and aerosols are colloidal solutions of :

The temperature above which micelle formation occurs is :

$50\mathrm{ }\;mL\mathrm{ }\;of\mathrm{ }\;1\;\mathrm{ }M$ oxalic acid is shaken with $0.5\;g$ wood charcoal. The final concentration of the solution after adsorption is $0.5\;\mathrm{ }M$. What is the amount of oxalic acid absorbed per gram of carbon?