**How many grams of FeCl**_{3}· 6 H_{2}O are contained in 20.0 mL of 1.5 M FeCl_{3}?

scott willis-
You can treat this as a simple unit conversion problem.
Solve it using the five step plan for converting units:
**Identify the unknown, including units.**You want to find grams of FeCl_{3}·6 H_{2}O.**Choose a starting point.**You have two pieces of information: 20.0 mL of solution and 1.5 M FeCl_{3}. Your unknown is not a fraction, so your starting point shouldn't be a fraction either. 1.5 M FeCl_{3}means 1 mol FeCl_{3}/1 L solution- it should be used as a conversion factor but not as a starting point. Your strategy is20.0 mL solution g FeCl _{3}·6 H_{2}O**List the connecting conversion factors.**Build a set of conversion factor 'stepping stones' to connect the starting point and the unknown. For example, you know (or can easily get) the molecular weight of the iron(III) chloride hexahydrate, so20.0 mL solution mol g FeCl _{3}·6 H_{2}Omolecular weight

g FeCl_{3}·6 H_{2}Og FeCl _{3}·6 H_{2}O_{3}to connect a volume of solution with moles of solute, so20.0 mL solution L solution molarity of

FeCl_{3}mol FeCl _{3}mol FeCl _{3}·6 H_{2}Omolecular weight

FeCl_{3}·6 H_{2}Og FeCl _{3}·6 H_{2}O**Multiply the starting measurement by conversion factors.**I'll let you try this.**Check the result: does the answer make sense?**Don't forget this step!

General Chemistry Online! How many grams of solute are in a certain volume of a solution of known molarity?

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Last Revised 02/23/18.URL: http://antoine.frostburg.edu/chem/senese/101/moles/faq/print-gsolute-from-mL-and-M.shtml