Advertisements
Advertisements
प्रश्न
Calculate molar conductivities at zero concentration for CaCl2 and NaCl.
Given: molar ionic conductivities of Ca2+, Cl–, Na+ ions are respectively, 104, 76.4, 50.1 Ω–1 cm–2 mol–1
उत्तर
Given:
`lambda_("Ca"^(2+))^0` = 104 Ω–1 cm2 mol–1,
`lambda_("Cl"^(-))^0` = 76.4 Ω–1 cm2 mol–1,
`lambda_("Na"^(+))^0` = 50.1 Ω–1 cm2 mol–1,
To find: Molar conductivity at zero concentration for CaCl2 and NaCl:
∧0 (CaCl2) and ∧0 (NaCl)
Formula: ∧0 = `"n"_+ lambda_+^0 + "n"_(-)lambda_(-)^0`
Calculation: According to Kohlrausch law,
∧0(CaCl2) = `lambda_("Ca"^(2+))^0` + `2lambda_("Cl"^(-))^0`
= 104 Ω–1 cm2 mol–1 + 2 × 76.4 Ω–1 cm2 mol–1
= 256.8 Ω–1 cm2 mol–1
∧0(NaCl) = `lambda_("Na"^(+))^0` + `lambda_("Cl"^(-))^0`
= 50.1 Ω–1 cm2 mol–1 + 76.4 Ω–1 cm2 mol–1
= 126.5 Ω–1 cm2 mol–1
Molar conductivity at zero concentration of CaCl2 is 256.8 Ω–1 cm2 mol–1
Molar conductivity at zero concentration of NaCl is 126.5 Ω–1 cm2 mol–1
APPEARS IN
संबंधित प्रश्न
0.05 M NaOH solution offered a resistance of 31.6 Ω in a conductivity cell at 298 K. If the cell constant of the cell is 0.367 cm-1, calculate the molar conductivity of NaOH solution.
Choose the most correct option.
Two solutions have the ratio of their concentrations 0.4 and ratio of their conductivities 0.216. The ratio of their molar conductivities will be ______.
Answer the following in brief.
Explain the effect of dilution of the solution on conductivity.
Answer the following:
What is Kohlrausch law of independent migration of ions? How is it useful in obtaining molar conductivity at zero concentration of a weak electrolyte? Explain with an example.
The molar conductivity and conductivity of AgNO3 solution is 121.4 Ω–1 cm2 mol–1 and 2.428 × 10–3 Ω–1 cm–1 at 25 °C. What is molar concentration of AgNO3 solution?
Give SI unit of resistivity.
Write applications of Kohlrausch’s Law.
State Kohlrausch law of independent migration of ions.
Write three important steps required to determine molar conductivity.
The molar conductances at infinite dilution `(∧_0)` for electrolytes B+A− and C+A− are 140 and 120 S cm2 mol−1. The molar conductance at infinite dilution for B+X− is 198 S cm2 mol−1. The `∧_0` (in S cm2 mol−1) of C+X− is __________.
The resistance of `1/10`M solution is 2.5 × 103 ohm. What is the molar conductivity of solution? (cell constant = 1.25 cm-1).
A conductivity cell having cell constant 8.76 cm−1, placed in 0.01 M solution of an electrolyte offered a resistance of 1000 ohms. What is the specific conductance of electrolytes?
The conductivity of 0.02 M solution of NaCl is 2.6 × 10−2 S cm−1. What is its molar conductivity?
The molar conductivities at zero concentration for Ca2+ and CaCl2 are 104 and 256.8 Ω−1 cm2 mol−1 respectively. The molar conductivity at zero concentration for Cl− is ____________.
The SI unit of resistivity and molar conductivity are respectively ____________.
The molar conductivities at infinite dilution for sodium acetate, HCI and NaCl are 91 S cm2 mol-1, 425.9 S cm2 mol-1 and 126.4 S cm2 mol-1 respectively. The molar conductivity of acetic acid at infinite dilution is ______.
What is the cell constant of `"N"/10 "KCl"` solution at 25°C, if conductivity and resistance of a solution is 0.0112 Ω−1 cm−1 and 55.0 Ω respectively?
The distance between electrodes of a conductivity cell is 0.98 cm and area of cross section is 1.96 cm2. What is the cell constant?
Conductivity of a conductor is ____________.
What is the unit of electrical conductance?
What is the conductivity of 0.01 M NaCl solution if resistance and cell constant of NaCl solution are 375 ohms and 0.5 cm-1 respectively at 298 K?
A conductivity cell dipped in 0.5 M KCl gives a resistance of 250 ohms. If the conductivity of KC I solution is 6.68 × 10-3 S cm-1, what is the cell constant?
Which of the following has least conductivity in aqueous solution?
Explain the determination of molar conductivity of a weak electrolyte at infinite dilution or zero concentration using Kohlrausch's law.
Define cell constant. Give its units.
