Advertisements
Advertisements
प्रश्न
0.01 m aqueous formic acid solution freezes at – 0.021°C. Calculate its degree of dissociation, Kf = 1.86 K kg mol–1.
Advertisements
उत्तर
ΔTf = iKfm
ΔTf = 0°C – (–0.021°C) = 0.021°C
m = 0.01 mol kg–1
0.021 = i × 1.86 K kg mol–1 × 0.01 mol kg–1
i = `0.021/(1.86 xx 0.01)` = 1.13
α = `(i - l)/(n - l)` = i – l because n = 2
Hence, α = 1.13 – 1 = 0.13 = 13%
APPEARS IN
संबंधित प्रश्न
A 0.1 m solution of K2SO4 in water has a freezing point of –4.3°C. What is the value of van’t Hoff factor if Kf for water is 1.86 K kg mol–1?
Answer the following in one or two sentences.
What is van’t Hoff factor?
Answer the following in one or two sentences.
How is van’t Hoff factor related to degree of ionization?
Answer the following in one or two sentences.
Which of the four colligative properties is most often used for molecular mass determination? Why?
At 25 °C, a 0.1 molal solution of CH3COOH is 1.35 % dissociated in an aqueous solution. Calculate the freezing point and osmotic pressure of the solution assuming molality and molarity to be identical.
A 0.15 m aqueous solution of KCl freezes at - 0.510 °C. Calculate i and osmotic pressure at 0 °C. Assume the volume of solution equal to that of water.
At T (K), the molar ionic conductivities of NH; and OH− at infinite dilution are 72 and 198 S cm2 mol−1 respectively. The molar conductivity of 0.01 M NH4OH solution at the same temperature is found to be 9 S cm2 mol−1. The percentage dissociation of NH4OH at this concentration is ____________.
It a centimolal aqueous solution of K3[Fe(CN)6] has degree of dissociation 0.78. What is the value of van't Hoff factor?
If the van't Hoff-factor for 0.1 M Ba(NO3)2 solution is 2.74, the degree of dissociation is ______.
0.6 g of a solute is dissolved in 0.1 L of a solvent which develops an osmotic pressure of 1.23 atm at 27°C. The molecular mass of the solute is ______.
Relationship between van't Hoff's factor (i) and degree of dissociation (α) is ______.
The osmotic pressure of a solution containing 10 g of cane sugar dissolved in 100 mL of water at 70°C is ____________.
Van't Hoff factor for K3[Fe(CN)6] is 3.333. What is it's percentage dissociation in water?
Why is observed molar mass of acetic acid in benzene is greater than actual molar mass?
Which of the following equations is NOT correct for van't Hoff factor?
Which of following 0.1 m aqueous solution exhibits highest osmotic pressure at 25°C?
Write modification of expressions of colligative properties with the help of van't Hoff factor.
Calculate the van't Hoff factor assuming the complete dissociation of NaBr in its aqueous solution.
Calculate ΔTb and boiling point of 0.05 m aqueous solution of glucose. (Given: Kb = 0.52 K m−1).
For 1 molal aqueous solution of the following compounds, which one will show the highest freezing point?
The depression in freezing point of 0.2 m aqueous solution of an electrolyte is 0.7 K. Calculate its percent degree of dissociation. [Kf for water = 1.86 K kg mol-1; n = 2]
