1.You have 0.50L of a gold chloride solution. You add 0.50L to the solution creating 1.0L of solution with a concentration of 0.26M. What was the original concentration? 2.You dissolve 0.26 moles of Co(NO3)2 in 0.30L of water. The resulting concentration is 0.87M. For an experiment, you need a concentration of 0.30M. What volume of water is needed for this concentration to result?

3. You dissolve 0.50 moles of NiCl2 in 0.40L of water. The resulting concentration is 1.3M. You increase the water in the solution until you have 0.80L. What is the new concentration?

You mix the pks of succinic acid are 4.21 and 5.64. how many gramsa graduate student at sdsu wants to measure the activity of a particular enzyme at ph 4.0. to buffer her reaction, she will use a buffer system based on one of the acids listed below, which acid is most appropriate for the experiment? of monosodium succinate (fw = 140 g/mol) and disodium succinate (fw = 162 g/mol) must be added to 1 l of water to produce a solution with a ph 5.28 and a total solute concentration of 100 mm? (assume the total volume remains 1 liter, answer in grams monosodium succinate, grams disodium succinate, respectively.) volumes of 0.05 m nah2po4 and 0.05 m na2hpo4 (pk's for phosphoric acid are 2.15, 6.82 and 12.38). which of the following best describes the resulting solution?

Suppose a lab group reports a ppercent yield of sand of 105. is it really possible to collect more sand than was originally represented? what is the possible explanation for the extra product?

8) a mixture of he, ne and ar has a pressure of 7.85 atm. if the ne has a mole fraction of 0.47 and 8) ar has a mole fraction of 0.23, what is the pressure of he? a) 4.2 atm b) 3.7 atm c) 5.5 atm d) 2.4 atm e) 1.8 atm