Which is correct in case of van der Waals adsorption?

1.  High temperature; low pressure

2.  Low temperature; high pressure

3.  Low temperature; low pressure

4.  High temperature; high pressure

The volumes of gases ${\mathrm{H}}_2, {\mathrm{CH}}_4, {\mathrm{NH}}_3 \mathrm{and} {\mathrm{CO}}_2$ adsorbed by 1 g of charcoal at 298 K in the decreasing order are

1. ${\mathrm{NH}}_3, {\mathrm{CO}}_2, C{\mathrm{H}}_4, {\mathrm{H}}_2$

2. ${\mathrm{CO}}_2, {\mathrm{NH}}_3, {\mathrm{H}}_2, C{\mathrm{H}}_4$

3. ${\mathrm{H}}_2, C{\mathrm{H}}_4, {\mathrm{CO}}_2, {\mathrm{NH}}_3$

3. $C{\mathrm{H}}_4, {\mathrm{NH}}_3, {\mathrm{CO}}_2, {\mathrm{H}}_2$

The coagulation of 200 mL of a positive colloid took place when 0.73 g HCl was added to it without changing the volume much. The flocculation value of HCl for the colloid is

1.  36.5

2.  100

3.  200

4.  150

The coagulating power of electrolytes with ions Na⁺,  Al³⁺, and Ba²⁺${ rise }^{}$for arsenic sulphide sol increases in the order :

1. $A{l}^{3+ }< B{a}^{2+ }< N{a}^{+}$

2. $N{a}^{+ }< B{a}^{2+ }< A{l}^{3+}$

3. $B{a}^{2+ }< N{a}^{+ }< A{l}^{3+}$

4. $A{l}^{3+ }< N{a}^{+ }< B{a}^{2+}$

The coagulation of 100 ml of colloidal solution of gold is completely prevented by the addition of 0.25 gm of a substance 'X' to it before adding 1 ml of 10%  NaCl solution. The gold number of 'X' is

1.  25

2.  0.25

3.  2.5

4.  0.025

When detergent is added in water, some properties are measured with respect to concentration. Choose the incorrect plot.

1.  

2.  

3.  

4.  

The decreasing order of coagulating power of an electrolyte to coagulate the ${\mathrm{As}}_2{\mathrm{S}}_3$ sol is

1.  $\mathrm{NaCl} > {\mathrm{Al}}_2{\left({\mathrm{SO}}_4\right)}_3 > {\mathrm{Ba}}_3{\left({\mathrm{PO}}_4\right)}_2$

2.  ${\mathrm{Ba}}_3{\left({\mathrm{PO}}_4\right)}_2 > NaCl > {\mathrm{Al}}_2{\left({\mathrm{SO}}_4\right)}_3$

3.  ${\mathrm{Al}}_2{\left({\mathrm{SO}}_4\right)}_3 > {\mathrm{Ba}}_3{\left({\mathrm{PO}}_4\right)}_2 > NaCl$

4.  $\mathrm{NaCl} >{\mathrm{Ba}}_3{\left({\mathrm{PO}}_4\right)}_2 > {\mathrm{Al}}_2{\left({\mathrm{SO}}_4\right)}_3$

Among the following, the surfactant that will form micelles in aqueous solution at the highest molar concentration

1.  ${\mathrm{CH}}_3 - {\left({\mathrm{CH}}_2\right)}_{14} - {{\mathrm{OSO}}_3}^{-} {\mathrm{K}}^{+}$

2.  ${\mathrm{CH}}_3 - {\left({\mathrm{CH}}_2\right)}_{10} - {\mathrm{COO}}^{-} {\mathrm{Na}}^{+}$

3.  ${\mathrm{CH}}_3 - {\left({\mathrm{CH}}_2\right)}_{11} - {{\mathrm{COO}}_3}^{-} {\mathrm{Na}}^{+}$

4.  ${\mathrm{CH}}_3 - {\left({\mathrm{CH}}_2\right)}_{15} - \stackrel{+}{\mathrm{N}}{\mathrm{H}}_3 {\mathrm{Br}}^{\mathrm{e}}$

If $\frac{22}{7}\mathrm{g}$ of charcoal having, active surface area 1000 ${\mathrm{m}}^2/\mathrm{g}$ is used for monolayer absorption of a gas having molecular radius ${10}^{-8}$ cm, then volume of the absorbed gas at STP is [Avogadro's number = $6 \times {10}^{23}$]

1.  11.2 L

2.  22.4 L

3.  7.46 L

4.  3.73 L

Emulsifying agent stabilized the emulsion of oil in water by

1.  Forming an interfacial film between suspended particles and the medium

2.  Dissolving the suspended particles into the medium completely

3.  Coagulating the suspended particles from the medium completely

4.  Converting the suspended particles into vapor completely