10. Determine the concentration of NaCl in the solution (g/1) , if the following results were obtained during potentiometric titration of 20.0 ml of a solution of 0 .2000 M AgNO_(3) 11. Determine the concentration of cadmium in the solution if D=0.7210^-5cm^2s^-1,m=2.0 mg/s,tau =4.4 s, and the current strength is 10mu A 12. The molar absorption coefficien t of silver in a complex with dithizone in solution at 462 nm is 30500 the minimum concentration in mol/1 of the complex of silver with dithizone, which can be determined by the photometric method at an absorbing layer thickness of 1=1 cm, if the minimum optical density recorded by the device is equals 0.01 .

Question

10. Determine the concentration of NaCl in the solution (g/1) , if the following results were obtained during potentiometric titration of 20.0 ml of a solution of 0 .2000 M AgNO_(3) 11. Determine the concentration of cadmium in the solution if D=0.7210^-5cm^2s^-1,m=2.0 mg/s,tau =4.4 s, and the current strength is 10mu A 12. The molar absorption coefficien t of silver in a complex with dithizone in solution at 462 nm is 30500 the minimum concentration in mol/1 of the complex of silver with dithizone, which can be determined by the photometric method at an absorbing layer thickness of 1=1 cm, if the minimum optical density recorded by the device is equals 0.01 .

Answer 1

10. To determine the concentration of NaCl in the solution, we can use the concept of stoichiometry and the balanced chemical equation for the reaction between NaCl and AgNO3.The balanced chemical equation for the reaction is:NaCl + AgNO3 → NaNO3 + AgGiven that the volume of the AgNO3 solution is 20.0 mL and its concentration is 0.2000 M, we can calculate the number of moles of AgNO3 using the formula:Moles of AgNO3 = Concentration of AgNO3 × Volume of AgNO3 solutionMoles of AgNO3 = 0.2000 M × 0.020 LMoles of AgNO3 = 0.004 molSince the reaction is a 1:1 stoichiometry, the number of moles of NaCl will be equal to the number of moles of AgNO3.Moles of NaCl = Moles of AgNO3Moles of NaCl = 0.004 molTo calculate the concentration of NaCl in the solution, we can use the formula:Concentration of NaCl = Moles of NaCl / Volume of solutionAssuming the volume of the solution is 1 L, the concentration of NaCl would be:Concentration of NaCl = 0.004 mol / 1 LConcentration of NaCl = 0.004 M or 4 g/LTherefore, the concentration of NaCl in the solution is 4 g/L.11. To determine the concentration of cadmium in the solution, we can use the formula for the diffusion coefficient:D = (m × τ) / (I × R)Where:D = Diffusion coefficient (cm^2/s)m = Mass transfer rate (mg/s)τ = Time (s)I = Current strength (A)R = Resistance (Ω)Given the values:D = 0.7210^-5 cm^2/sm = 2.0 mg/sτ = 4.4 sI = 10 μA = 10^-8 AWe can rearrange the formula to solve for the concentration of cadmium:Concentration of cadmium = (m × τ) / (D × I)Substituting the given values:Concentration of cadmium = (2.0 mg/s × 4.4 s) / (0.7210^-5 cm^2/s × 10^-8 A)Concentration of cadmium = 1.176 × 10^11 mg/LTherefore, the concentration of cadmium in the solution is 1.176 × 10^11 mg/L.12. To calculate the minimum concentration of the complex of silver with dithizone, we can use the Beer-Lambert law:A = ε × c × lWhere:A = Absorbanceε = Molar absorption coefficient (L·mol^-1·cm^-1)c = Concentration (mol/L)l = Path length (cm)Given the values:ε = 30500 L·mol^-1·cm^-1A = 0.01l = 1 cmWe can rearrange the formula to solve for the concentration:c = A / (ε × l)c = 0.01 / (30500 × 1)c = 3.278 × 10^-7 mol/LTherefore, the minimum concentration of the complex of silver with dithizone that can be determined by the photometric method is 3.278 × 10^-7 mol/L.

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