how cam the amount of chlorine in [Ni(NH3)6]Cl2 be determined
Dissolve the Ni salt in water and ppt AgCl to determine gravimetrically or titrate with either the Mohr method or the Volhard method. You can get very good results with any of the three procedures.
To determine the amount of chlorine in [Ni(NH3)6]Cl2, you can use a technique called volumetric analysis, specifically titration. Here's how you can proceed:
1. Prepare a solution of a known concentration of a silver nitrate (AgNO3) solution. Silver nitrate reacts with chloride ions (Cl-) to form a white precipitate of silver chloride (AgCl).
2. Take a measured volume of the [Ni(NH3)6]Cl2 solution in a flask. Add a few drops of a potassium chromate (K2CrO4) indicator solution. The addition of the indicator will cause the color of the solution to change from yellow to reddish-orange.
3. Start adding the silver nitrate solution from a burette into the flask containing the [Ni(NH3)6]Cl2 solution. The silver nitrate reacts with the chloride ions in the [Ni(NH3)6]Cl2 solution to form a white precipitate of silver chloride (AgCl). The reaction can be represented as follows:
AgNO3 + Cl- → AgCl + NO3-
4. Keep adding the silver nitrate solution until a color change is observed from reddish-orange to a permanent light pink or red color. This color change indicates that all of the chloride ions in the [Ni(NH3)6]Cl2 solution have reacted with the silver ions to form silver chloride.
5. Record the initial and final volume readings on the burette to determine the volume of silver nitrate solution that was required to react completely with the chloride ions.
6. From the reaction stoichiometry, it can be inferred that one mole of silver nitrate reacts with two moles of chloride ions. Using this relationship and the concentration of the silver nitrate solution, you can calculate the number of moles of chloride ions present in the [Ni(NH3)6]Cl2 solution.
7. Finally, knowing the molar mass of chlorine (Cl), you can determine the mass or amount of chlorine present in the [Ni(NH3)6]Cl2 complex.
It's important to note that an accurately known concentration of the silver nitrate solution and precise measurements during the titration process are crucial to obtaining reliable results.