Preparing Solutions

 

   1) What volume of a 0.0010 M solution of Zn(NO3)2 would be required to prepare a 6.0 nM solution of Zn2+ in a 500-mL flask?

(a) 6.0 µL

(b) 1.5 µL

(c) 3.0 µL

(d) 12 µL

 

   2) You are required to prepare 2.00 L of a solution containing 2.000 x 10-3 mol/L of Cu2+. Which of the following procedures are correct?

(a) Dissolve 0.2542 g of copper metal in nitric acid, add to a 2.000-L volumetric flask, dilute to the mark with deionized water and mix well.

(b) Dissolve 0.1271 g of copper metal in nitric acid, add to a 2.000-L volumetric flask, dilute to the mark with deionized water and mix well.

(c) Dissolve 0.5000 g of CuSO4•5H2O in deionized water, add to a 2.000-L volumetric flask, dilute to the mark with deionized water and mix well.

(d) Dissolve 1.00 g of CuSO45H2O in deionized water, add to a 2.000-L volumetric flask, dilute to the mark with deionized water and mix well.

 

   3) You want to prepare 500. mL of a 0.0470 M solution of NaNO3. Which of the following would give the best results?

(a) Accurately mass out 2.00 g NaNO3.

     Dissolve the solid in 100. mL distilled water in a beaker.

      Carefully pour the solution into a 500-mL volumetric flask.

     Rinse the beaker with 20. mL distilled water and add to volumetric flask.

     Carefully add 380. mL distilled water to the volumetric flask and mix well.

(b) Accurately mass out 2.00 g NaNO3.

      Dissolve the solid in some tap water in a beaker.

     Carefully pour the solution into a 500-mL volumetric flask.

     Rinse the beaker with tap water and add to volumetric flask.

     Carefully fill the flask with distilled water to the mark and mix well.

(c) Accurately mass out 2.00 g NaNO3.

     Dissolve the solid in some distilled water in a beaker.

     Carefully pour the solution into a 500-mL volumetric flask.

     Rinse the beaker with distilled water and add to volumetric flask.

     Carefully fill the flask with distilled water to the mark and mix well.

(d) Accurately mass out 2.00 g NaNO3.

     Dissolve the solid in 498 mL of distilled water and mix well.

 

   4) What volume of a 0.0020 M solution of Zn(NO3)2 would be required to prepare a 200 nM solution of Zn2+ in a 500-mL flask?

(a) 25 µL

(b) 5.0 µL

(c) 2.5 µL

(d) 0.25 µL

 

   5) You are required to prepare 250. mL of a solution containing 5.000 x 10-2 mol L-1 of Cu2+. Which of the following procedures are correct?

(a) Dissolve 3.177 g of copper metal in nitric acid, add to a 250-mL volumetric flask, dilute to the mark with deionized water and mix well.

(b) Dissolve 0.7942 g of copper metal in nitric acid, add to a 250-mL volumetric flask, dilute to the mark with deionized water and mix well.

(c) Dissolve 12.484 g of CuSO4•5H2O in deionized water, add to a 250-mL volumetric flask, dilute to the mark with deionized water and mix well.

(d) Dissolve 3.12 g of CuSO45H2O in deionized water, add to a 250-mL volumetric flask, dilute to the mark with deionized water and mix well.

 

   6) You want to prepare 500. mL of a 0.0909 M solution of LiC2H3O2. Which of the following would give the best results?

(a) Accurately mass out 3.00 g LiC2H3O2.

     Dissolve the solid in 100. mL distilled water in a beaker.

      Carefully pour the solution into a 500-mL volumetric flask.

     Rinse the beaker with 20. mL distilled water and add to volumetric flask.

     Carefully add 380. mL distilled water to the volumetric flask and mix well.

(b) Accurately mass out 3.00 g LiC2H3O2.

      Dissolve the solid in some distilled water in a beaker.

     Carefully pour the solution into a 500-mL volumetric flask.

     Rinse the beaker with distilled water and add to volumetric flask.

     Carefully fill the flask with distilled water to the mark and mix well.

(c) Accurately mass out 3.00 g LiC2H3O2.

     Dissolve the solid in some distilled water in a beaker.

     Carefully transfer the solid into a 1.00-L volumetric flask.

     Add 500.0 mL distilled water to the flask and mix well.

(d) Accurately mass out 3.00 g LiC2H3O2.

     Carefully transfer the solid to a beaker.

      Dissolve the solid in 497 mL distilled water and mix well.

 

   7) What volume of a 0.0015 M solution of MgCl2 would be required to prepare a 73 nM solution of Mg2+ in a 150-mL flask?

(a) 1.5 µL

(b) 7.3 µL

(c) 15 µL

(d) 0.53 µL

 

   8) You have 500.0 mL of a 3.0 M solution of NH3 in a volumetric flask and want to dilute it to a 1.0 M solution. Which of the following procedures would give you the best results?

(a) Transfer the NH3 solution to a 1.5-L volumetric flask.

     Rinse the original volumetric flask with 50. mL of distilled water and add washings to the 1.5-L volumetric flask.

      Carefully add 950. mL of distilled water to the volumetric flask and mix well.

(b) Transfer the NH3 solution to a large beaker.

      Rinse the original volumetric flask with 50. mL distilled water and add washings to the beaker.

     Carefully add 950. mL of distilled water to the beaker and mix well.

(c) Transfer the NH3 solution to large beaker.

     Carefully fill a 1.0-L volumetric flask with distilled water to the mark.

     Pour the contents of the volumetric flask into the beaker with the original solution and mix well.

(d) Transfer the NH3 solution to a 1.5-L volumetric flask.

     Rinse the original volumetric flask with distilled water and add washings to the 1.5-L volumetric flask.

      Carefully fill the flask with distilled water to the mark and mix well.

 

 

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