Knowee
Questions
Features
Study Tools

Calculate Van't Hoff factor for an aqueous solution of K3 [Fe(CN)6] if the degree of dissociation(α) is 0.852. What will be boiling point of this solution if its concentration is 1 molal? (Kb=0.52 Kkg/mol)

Question

Calculate Van't Hoff factor for an aqueous solution of K3 [Fe(CN)6] if the degree of dissociation(α) is 0.852. What will be boiling point of this solution if its concentration is 1 molal? (Kb=0.52 Kkg/mol)

🧐 Not the exact question you are looking for?Go ask a question

Solution

The Van't Hoff factor (i) is used to account for the effect of solute particles in solutions on colligative properties. It is defined as the ratio of moles of particles in solution to the moles of solute dissolved.

For the compound K3[Fe(CN)6], it dissociates in water as follows:

K3[Fe(CN)6] → 3K+ + [Fe(CN)6]3-

So, theoretically, one molecule of K3[Fe(CN)6] should produce 4 particles (3 K+ ions and 1 [Fe(CN)6]3- ion).

However, since the degree of dissociation (α) is given as 0.852, not all of the K3[Fe(CN)6] molecules dissociate.

The Van't Hoff factor (i) can be calculated as follows:

i = 1 + (n-1)α

where n is the number of particles produced by the solute (in this case, 4), and α is the degree of dissociation.

i = 1 + (4-1)0.852 = 1 + 30.852 = 3.556

So, the Van't Hoff factor for this solution is 3.556.

The boiling point elevation of a solution (ΔTb) can be calculated using the formula:

ΔTb = iKbm

where i is the Van't Hoff factor, Kb is the ebullioscopic constant (in this case, 0.52 Kkg/mol), and m is the molality of the solution (in this case, 1 molal).

ΔTb = 3.5560.521 = 1.84912 K

So, the boiling point of the solution will be 1.84912 K higher than the boiling point of pure water (which is 373.15 K at standard pressure).

Therefore, the boiling point of this solution is 373.15 K + 1.84912 K = 374.99912 K.

This problem has been solved

Similar Questions

14. 0.2 m aqueous solution of KCl freezes at -0.68°C calculate van't Hoff factor. kf, for water is 1.86 K kg mol¹. ​

19.5 g of CH2FCOOH is dissolved in 500g of water. The depression in the freezing point of water observed in 1.0 C. Calculate the van't Hoff factor and dissociation

The Van't Hoff factor for 0.1 M La (NO3)3 solution is found to be 2.74 the percentage dissociation of the salt is :

A certain substance X has a normal boiling point of 146.3°C and a molal boiling point elevation constant =Kb·1.47°C·kgmol−1. Calculate the boiling point of a solution made of 6.083g of urea NH22CO dissolved in 200.g of X.Round your answer to 4 significant digits.

51. What is the ΔH° at 298 K of the given reaction?*- 3.8 kJ/mol3.8 J/mol0Cannot defined

1/3

Upgrade your grade with Knowee

Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.