solution until the volume of the solution is exactly by eno20265

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									1. Water is added to 25.0 mL of a 0.866 M KNO3 solution until the volume of the
   solution is exactly 500 mL. What is the concentration of the final solution? 0.0433 M

2. You have 505 mL of a 0.125 M HCl solution and you want to dilute it to exactly
   0.100 M. How much water should you add? 126.25 mL

3. Calculate the molarity of each of the following solutions:
(a) 6.57 g of methanol (CH3OH) in 1.57 x 102 mL of solution. 1.31 M

(b) 10.4 g of calcium chloride (CaCl2) in 2.20 x 102 mL of solution. 0.426 M

(c) 7.82 g of naphthalene (C10H8) in 85.2 mL of benzene solution. 0.717 M

4. How many grams of NaCl are required to precipitate most of the Ag+ ions from
   2.50 x 102 mL of 0.0113 M AgNO3 solution. Write the net ionic equation for the reaction.
   0.165 g

5. A sample of 0.6760 g of an unknown compound containing barium ions (Ba2+) is
   dissolved in water and treated with an excess of Na2SO4. If the mass of the BaSO4
   precipitate formed is 0.4105 g, what is the percent by mass of Ba in the original unknown
   compound? 35.74%

6. Calculate the volume in mL of a 1.420 M NaOH solution required to titrate the following
    solutions:
(a) 25.00 mL of a 2.430 M HCl solution 42.78 mL

(b) 25.00 mL of a 4.500 M H2SO4 solution 158.5 mL

(c) 25.00 mL of a 1.500 M H3PO4 solution 79.23 mL

7. Vinegar is an aqueous solution of acetic acid, HC2H3O2, which is often written as
   HAc for simplicity. A 12.5 mL sample of vinegar was titrated with a 0.504 M solution of
   NaOH. The titration required 15.40 mL of the NaOH solution in order to reach the
   endpoint. What is the molar concentration of HAc in vinegar? 0.621 M

                               NaOH + HAc → NaAc + H20

8. The concentration of a hydrogen peroxide solution can be conveniently determined by
   titration against a standardized potassium permanganate solution in an acidic medium
   according to the following equation:

                 2 MnO4– + 5 H2O2 + 6 H+ → 5 O2 + 2 Mn2+ + 8 H2O

   If 36.44 mL of a 0.01652 M KMnO4 solution are required to completely oxidize
   25.00 mL of a H2O2 solution, calculate the molarity of the H2O2 solution. 0.0602 M
9. The alcohol content in a 10.0 g sample of blood from a driver required 4.23 mL of
   0.07654 M K2Cr2O7 for titration. Should police prosecute for intoxication if the legal
   limit is 0.1 % by mass? 0.223%

        3 EtOH + 2 K2Cr2O7 + 8 H2SO4 → 3 HOAc + 2 Cr(SO4)3 + 2 K2SO4 + H2O

10. How many mL of a 0.206 M HI solution are needed to reduce 22.5 mL of a
    0.374 M KMnO4 solution? 204 mL

             10 HI + 2 KMnO4 + 3 H2SO4 → 5 I2 + 2 MnSO4 + K2SO4 + 8 H2O

11. Calculate the concentration of acid or base remaining when 10.7 mL of 0.211 M HNO3
    are added to 16.3 mL of 0.258 NaOH. 0.0722 M

                            HNO3 + NaOH → NaNO3 + H2O

								
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