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Title: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: Boedecjt01 on Oct 25, 2016 I have tried using Molarity= Moles of Solute/Liters of Solution, but i cannot figure the answer out. If you can only get the first two questions, that is okay, thank you!
1) Calculate the amount of potassium ferrocyanide trihydrate [K4Fe(CN)6•3H2O] needed to prepare 250 ml of 0.025 M solution. 2) Calculate the amount of zinc sulfate heptahydrate [ZnSO4•7H2O] needed to prepare 250 ml of 0.050 M solution. 3) Assuming that the actual molarities of your stock solutions are equal to the target molarities given above, calculate what titration volume of zinc sulfate would be expected for titrating a 25.00 ml aliquot of the ferrocyanide solution for each of the five possible reactions presented below: K4Fe(CN)6(aq) + ZnSO4(aq) -----> K2ZnFe(CN)6(s) + K2SO4(aq) K4Fe(CN)6(aq) + 2 ZnSO4(aq) ----> Zn2Fe(CN)6(s) + 2 K2SO4(aq) 2 K4Fe(CN)6(aq) + ZnSO4(aq) ----> K6Zn[Fe(CN)6]2(s) + K2SO4(aq) 2 K4Fe(CN)6(aq) + 3 ZnSO4(aq) ----> K2Zn3[Fe(CN)6]2(s) + 3 K2SO4(aq) 3 K4Fe(CN)6(aq) + 2 ZnSO4(aq) ----> K8Zn2[Fe(CN)6]3(s) + 2 K2SO4(aq) Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: bio_man on Oct 25, 2016 For #1 and #2, see if this helps before I continue
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: Boedecjt01 on Oct 25, 2016 Where did the 3 come from on the outside of the bracket in problem 1?
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: bio_man on Oct 26, 2016 I thought it contained it... opps.
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: psyche360 on Oct 26, 2016 The MWt of [K4Fe(CN)6•3H2O] (C6H6FeK3N6O3) = 383.3 g
250 mL of 0.025 M K4Fe(CN)6•3H2O contains (250/1000)×0.025 = 6.25×10^-3 mole Hence amount needed = (6.25×10^-3)×383.3 = 2.40 g (should only be 2 sig figs) Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: Boedecjt01 on Oct 26, 2016 I have tried using Molarity= Moles of Solute/Liters of Solution, but i cannot figure the answer out. I have the first two, but the third question is confusing.
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: bio_man on Oct 26, 2016 I'm unsure how to tackle it too :(
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: kenyonb on Oct 25, 2018 Thank you
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: Jnm907 on Oct 20, 2021 .
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: SMR on Dec 1, 2021 thank you
Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: jayyyz214 on Dec 2, 2021 3. Molarity of ZnSO4. 7H2O = 0.050 M
Volume = 250 mL = 0.250 L Moles of ZnSO4. 7H2O = Molarity * Volume = 0.050 M * 0.250 L = 0.0125 moles Molar mass of ZnSO4. 7H2O = 287.5496 g/mol Mass of ZnSO4. 7H2O = Moles * Molar mass = 0.0125 moles * 287.5496 g/mol = 3.59 g Title: Re: Calculate the amounts of the substance in order to prepare a certain amount of the solution Post by: KnottyMonkey656 on Dec 14, 2021 .
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