Gold number gives:

Important Questions on Surface Chemistry

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Which mixture of the solutions will lead to the formation of negatively charged colloidal $\left[\mathrm{A}\mathrm{g}\mathrm{I}\right]{\mathrm{I}}^{-}$ sol?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Which property of colloidal solution is independent of charge on the colloidal particles?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Gold numbers of some colloids are Gelatin: $0.005-0.01$, Gum Arabic: $0.15-0.25$, Oleate: $0.04-1.0$, Starch: $15-25$. Which among the following is a better protective colloid?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Which property of colloids is not dependent on the charge on colloidal particles?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

The haemoglobin and the gold sol are examples of

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Among the following, the incorrect statement about colloids is:

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

The Tyndall effect is observed only when the following conditions are satisfied,

$\left(\mathrm{i}\right)$ The diameter of the dispersed particles is much smaller than the wavelength of the light used.

$\left(\mathrm{ii}\right)$ The diameter of the dispersed particle is not much smaller than the wavelength of the light used.

$\left(\mathrm{iii}\right)$ The refractive indices of the dispersed phase and dispersion medium are almost similar in magnitude.

$\left(\mathrm{iv}\right)$ The refractive indices of the dispersed phase and dispersion medium differ greatly in magnitude.

HARD

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

A sol of $\mathrm{Agl}$ is prepared by mixing equal volumes of $0.1 \mathrm{M} {\mathrm{AgNO}}_3$ and $0.2 \mathrm{M} \mathrm{Kl}$, which of the following statement is correct?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

For coagulation of arsenious sulphide sol, which of the following salt solutions will be most effective?

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Among the following, the false statement is:

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

As per Hardy-Schulze formulation, the flocculation values of the following for ferric hydroxide sol are in the order:

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Identify the correct statements from the following
I) Protective power of a lyophobic colloid is expressed by gold number
II) Haemoglobin is a positively charged sol
III) Metal sols are prepared by peptization process
IV) Colloidal solution and true solution can be distinguished by Tyndall effect

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Measuring Zeta potential is useful in determining which property of colloidal solution?

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

The correct option among the following is.

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

During electro-osmosis of $\mathrm{Fe}{\left(\mathrm{OH}\right)}_3$ sol,

EASY

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

The phenomenon of Tyndall effect is not observed in

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Which of the following has the highest coagulating power for ${\mathrm{As}}_2{\mathrm{S}}_3$ colloid?

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

The coagulating power of electrolytes having ions ${\mathrm{Na}}^{+}$,  ${\mathrm{Al}}^{3+}$ and ${\mathrm{Ba}}^{2+}$ for arsenic sulphide sol increases in the order,

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Write notes on protection of colloids.

MEDIUM

Chemistry>Physical Chemistry>Surface Chemistry>Protection of Lyophobic Sols and Gold Number

Why are lyophilic colloids used as protective colloids?