Problem- Calculate the volume (mL) of 30.0% (w/w) H2O2 needed to prepare 50.0 mL 3.6 M H2O2. The density of 30.0% (w/w) H2O2 is 1.11 g/mL at 25 degrees C.
Note- 30% (w/w) means there are 30g H2O2 in 100g solution.
Hint- Start with the volume (50mL) and molarity (3.6M) of the desired solution and determine the moles of H2O2 required to make it. From the number of moles of H2O2 required, you can calculate the number of grams of H2O2 required. Then, you can calculate the mass of concentrated H2O2 solution containing the required grams of H2O2 (see Note above). Lastly, knowing the mass of concentrated H2O2 solution required, you can calculate its required volume using its density.
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