Procedure:
1. Mix 20.0ml of Pb(NO3)2 and 40.0ml of NH4CL in a Erlenmeyer flask then label the solution A
2. Do the same for B but use 25.0ml of Pb(NO3)2 instead of 20.0ml of Pb(NO3)2 and use 35.0ml of NH4CL instead of 40.0ml of NH4CL
3. For C use 30.0ml of Pb(NO3)2 and 30.0ml of NH4CL
4. For D use 35.0ml of Pb(NO3)2 and 25.0ml of NH4CL
5. Add 20ml of distilled water to all four solutions
6. Shake each of the four solutions every 5 minutes for half an hour
7. Filter off the precipitate in every solution into a beaker
8. Pipette 10ml of solution A into a 50ml flask and then do it again into another 50ml flask
9. Do step 8 for solution B, C, D
10.

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