Place ~0.8 g Fe(NO3)3·9 H2O into a 10 mL volumetric flask and dissolve to the vo
ID: 1042641 • Letter: P
Question
Place ~0.8 g Fe(NO3)3·9 H2O into a 10 mL volumetric flask and dissolve to the volumetric line with 0.1 M HNO3(aq). (Make sure you pre-rinse the volumetric flask with the 0.1 M HNO3(aq) solution before making the solution. Also, 9 waters of hydration (·9H2O) are present in this chemical, and must be included in the formula weight calculation.) Record the exact mass of iron nitrate used and show the calculation for the solution concentration in your observations.
Before lab, create a plan for the dilution of the Fe(NO3)3(aq) solution created above with DI water. This plan should be clearly outlined in your ELN. Create enough 0.0020 M Fe(NO3)3
How do I go about solving for the dilution plan?
Explanation / Answer
Yes you have to calculate the mass of both Fe(NO3)3 and 9 H2O components.
molar mass of Fe(NO3)3 = 242 g/mol
molar mass of H2O = 18 g/mol
molar mass of compound Fe(NO3)3.9H2O = 242 + 9*18 = 404 g/mol
Number of moles of compound = 0.8/404 = 1.98 * 10^-3 moles
According to given conditions we to consider the mass of water molecules also.