10. Determine the concentration of NaCl in the solution (g/1) , if the following results were obtained during potentiometri 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 . Calculate 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

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10. Determine the concentration of NaCl in the solution (g/1) , if the following results were obtained during potentiometri 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 . Calculate 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 given information about the titration of AgNO3.Given:- Volume of NaCl solution: 20.0 mL- Concentration of AgNO3 solution: 0.2000 MThe balanced chemical equation for the reaction between NaCl and AgNO3 is:NaCl + AgNO3 → NaNO3 + AgClFrom the balanced equation, we can see that 1 mole of NaCl reacts with 1 mole of AgNO3.To find the concentration of NaCl, we need to calculate the number of moles of AgNO3 used in the titration.Number of moles of AgNO3 = Concentration of AgNO3 × Volume of AgNO3 solutionNumber of moles of AgNO3 = 0.2000 M × (20.0 mL / 1000 mL/L)Number of moles of AgNO3 = 0.004 molSince the reaction is 1:1, the number of moles of NaCl will be the same as the number of moles of AgNO3.Now, we can calculate the concentration of NaCl using the formula:Concentration of NaCl = Number of moles of NaCl / VolumeCl solutionConcentration of NaCl = 0.004 mol / (20.0 mL / 1000 mL/L)Concentration of NaCl = 0.2000 MTherefore, the concentration of NaCl in the solution is 0.2000 M.11. To determine the concentration of cadmium in the solution, we can use the given values and the formula for the relationship between current, charge, and concentration.Given:- Diffusion coefficient (D) = 0.7210^-5 cm^2/s- Mass flow rate (m) = 2.0 mg/s- Time (τ) = 4.4 s- Current strength (I) = 10 μAThe relationship between current, charge, and concentration is given by the formula:I = (m / (z × F)) × (1 / (D × τ))Where:- I is the current strength- m is the mass flow rate- z is the charge of the cadmium ion (2 for Cd^2+)- F is the Faraday constant (96485 C/mol)- D is the diffusion coefficient- τ is the timeRearranging the formula to solve for the concentration:Concentration = (m × D × τ) / (I × z × F)Substituting the given values:Concentration = (2.0 mg/s × 0.7210^-5 cm^2/s × 4.4 s) / (10 μA × 2 × 96485 C/mol)Concentration = 1.57 × 10^-6 mol/LTherefore, the concentration of cadmium in the solution is 1.57 × 10^-6 mol/L.12. To calculate the minimum concentration of the complex of silver with dithizone, we can use the Beer-Lambert law.Given:- Molar absorption coefficient (ε) = 30500 L/mol·cm- Absorbing layer thickness (l) = 1 cm- Minimum optical density (A) = 0.01The Beer-Lambert law states that the optical density (A) is directly proportional to the concentration (c) of the absorbing species:A = ε × c × lRearranging the formula to solve for the concentration:c = A / (ε × l)Substituting the given values:c = 0.01 / (30500 L/mol·cm × 1 cm)c = 3.28 × 10^-7 mol/LTherefore, the minimum concentration of the complex of silver with dithizone that can be determined by the photometric method is 3.28 × 10^-7 mol/L.

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