# Van’t Hoff Factor (i) worksheet

The measure of the solute upon vapour pressure, osmotic pressur and freezing point depression is called Van’t Hoff Factor (i). It is the ratio between the actual concentration of a particles of dissolved substance and the concentration of the substance as calculated from its mass.

The van’t factor for non-electrolytes dissolved in water is usally 1.

Here you can find some questions related to Van’t Hoff factor (i) and it’s answer:

Questions:

1. The benzoic acid undergoes dimerization in benzene solution, the van’t Hoff factor ‘i’ is related to the degree of association ‘x’ of the acid as:

(a)    i = (1 + x)

(b)   i = (1 – x)

(c)    i = (1 – x/2)

(d)   i = (1 + x/2)

2. Which of the following solutions will have the highest boiling point?

(a)    0.1 M $FeCl_3$

(b)   0.1 M NaCl

(c)    0.1 M $BaCl_2$

(d)   0.1 M urea $(NH_2CONH_2)$

3. The freezing point of equimolal aqueous solutions will be highest for:

(a)    $La(NO_3)_3$

(b)   $Ca(NO_3)_2$

(c)    $C_6H_5NH_3Cl$

(d)   $C_6H_{12}O_6$

4. Assuming complete dissociation, which one of the following will have a van’t Hoff factor of 2?

(a)    $CaSO_4$

(b)   $H_2SO_4$

(c)    sucrose

5. Phenol (mol. wt. 94) is dimerised to 60% in a solvent, the observed molecular weight of phenol will be:

(a)    100

(b)   134.2

(c)    Less than 94

(d)   150

6. Van’t Hoff factor for a dilute solution of sodium argento cyanide is:

(a)    2 0

(b)   .25

(c)    3.0

(d)   0.50

7. Which shows maximum osmotic pressure in 1 M solution?

(a)    $KNO_3$

(b)   $Na_2SO_4$

(c)    $(NH_4)_3PO_4$

(d)   $CaCl_2$

8. The values of observed and calculated molecular weights of silver nitrate are 92.64 and 170 respectively. The degree of dissociation of silver nitrate is:

(a)    60%

(b)   83.5%

(c)    56.7%

(d)   70.23%