posted by chelsea .
Hey, I am having a real hard time getting the answers to the problems. Any help would be greatly aprreciated!
1. When 11 mL of a solution containing 2.9 M AlBr3 is diluted to 33 mL, a dilute solution is formed. What is the Br- concentration in 25 mL of the dilute solution?
2. A stock solution is prepared by adding 23 mL of 1.2 M AlCl3 to enough water to make 76 mL. What is the Cl- concentration of 40 mL of the stock solution?
3. When 26 mL of a 335 mL stock solution containing 2.01 M Na2S is diluted to 76 mL, how many moles of Na+ are in the new solution?
4. When 48 mL of a solution containing 4.1 M AlCl3 is diluted to 50 mL, a dilute solution is formed. How many moles of Al3+ ions are contained in 14 mL of the dilute solution?
5. How many milliliters of a 135 mL solution of 1.7 M Na3PO4 must be used to make 71 mL of a solution that has a concentration of .6 M Na+?
6. A 11 mL sample of a solution of AlBr3 was diluted with water to 21 mL. A 17 mL sample of the dilute solution was found to contain 0.047 moles of Br-. What was the concentration of AlBr3 in the original undiluted solution?
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