451.

Which of the following is incorrect for physisorption?

• Reversible

• Increases with increase in temperature.

• Low heat of adsorption.

• Increases with increase in surface area.

When a sulphur sol is evaporated sulphur is obtained .On mixing with water sulphur sol is not formed .The sol is :

• lyophilic

• reversible

• hydrophobic

• hydrophilic

An example for autocatalysis is :

• oxidation of NO to NO₂

• oxidation of SO₂ to SO₃

• decomposition of KClO₃ to KCl and O₂

• oxidation of oxalic acid by acidified KMnO₄

Correct equation of Freundlich isotherm is

• $\log \left(\frac{\mathrm{x}}{\mathrm{m}}\right)= \mathrm{logk} + \frac{1}{\mathrm{n}}\log \mathrm{c}$

• $\log \left(\frac{\mathrm{x}}{\mathrm{m}}\right) = \log \mathrm{c}+\frac{1}{\mathrm{n}}\log \mathrm{k}$

• $\log \left(\frac{\mathrm{x}}{\mathrm{m}}\right)= \log \mathrm{c} +\frac{1}{\mathrm{k}} \log \mathrm{c}$

• $\log \left(\frac{\mathrm{x}}{\mathrm{m}}\right) = \mathrm{logk} + \frac{1}{\mathrm{k}}\log \mathrm{c}$

A lyophobic colloid is :

• As₂S₃

• starch

• agar - agar

• gelatin

Which of the following is correct according to Freundlich adsorption isotherm ?

• $\frac{\mathrm{x}}{\mathrm{m}}$ $\propto$ p^o

• $\frac{\mathrm{x}}{\mathrm{m}}$ $\propto$ p

• $\frac{\mathrm{x}}{\mathrm{m}}$ $\propto$ $\frac{1}{\mathrm{p}}$

• $\frac{\mathrm{x}}{\mathrm{m}}$ $\propto$ p^1/n

The rust of iron is catalysed by which of the following ?

• Fe

• O₂

• Zn

• H⁺

In coagulating the colloidal solution of As₂S₃ .which has the minimum coagulating value ?

• NaCl

• KCl

• BaCl₂

• AlCl₃

Which one of the following is not a surfactant?

• 

• CH₃-(CH₂)₁₄-CH₂-NH₂

• CH₃-(CH₂)₁₆-CH₂OSO₂^-Na⁺

• OHC-(CH₂)₁₄-CH₂-COO^-Na⁺

The size of colloidal particle is :

• 10^-3 to 10⁹ m

• 10^-9 to 10^-12 m

• 10^-6 to 10^-9 m

• 10^-12 to 10^-19 m