Reference no: EM13775770

1. Calculate the molarity of sodium in 1.9g of sodium acetate diluted in 100 mL of DI water.

2. Calculate the concentration of both sodium and acetate ions in problem 1 in units of mg/mL, [ig-/L, mg/L, and lig/mL.

3. Calculate the concentration of 29 % NH3 with density of 0.88 g/mL.

4. You have been provided 100 m11 of a 1000 pt 111 barium standard. What volume of this standard must be diluted to a final volume of 50 mL, using DI water to produce a 30 ughni standard?

5. Given a full 100 mL of the same standard provided in question 4, calculate the amount of standard and final volume required to produce a series of standards at these concentrations: 1 ppm, 3 ppm, 10 ppm, 25 ppm, 50 ppm and 100 ppm. You will need at least 10 mL of each standard. You have a 1 m1_, class A pipette, a 5 mL, class A pipette and a 10 mL Class A pipette, all calibrated TD. You do not have the ability to use volumes other than had you have a pipette for (Le. you can not use 1.5 ml since YOU do not have a pipette calibrated for 0.5 ml).

6. Given a full 100 m1_, of the same standard from problem 4 and 100 m1_, of a 100 ppm Yttrium standard, calculate the amount of the Ba standard, the I standard and DI water to produce a series of 10 ml standards containing 10 ppm Ba„ 25 ppm Ba, 50 ppm Ba, 100 ppm Ba. All standards should also contain 10 ppm I.

7. Given the following data obtained on the AA, generate a linear calibration curve and determine the concentration of Ba in the unknown sample.

Concentration Absorbance

(mg/L) (Au)

            1.0       0.09

            2.5       0.22

            4.0       0.37

            5.0       0.43

            6.0       0.49

Unknown        0.38

8. Describe the proper procedure for weighing out a specified amount of a standard material.

9. You are asked to measure out 0.1960g of ferrous ammonium sulfate hexahydrate to produce a 0.0050 M solution for a calibration curve. What if you are unable to measure out 0.1960g but instead were only able to measure 0.1749g? What do you do so that you can use this solution, assuming you have no more material?

10. When using a class A pipette that is calibrated TD, do you let the solution run out of the pipette until it stops on its own or do you blow out the pipette with your pipette bulb? What about for a pipette calibrated TR? What do the definitions TD and TR stand for?