Fe = 55.8; S = 32; O= 16; H 1 %3D 10 10g of an impure iron(11) salt were dissolved in water and made up to 200 cm of solution. 20cm of this solution; acidified with dilute sulphuric acid, required 25 cm of 0.04 M KMNO4(aq) before a faint pink colour appeared. (a) Write a balanced ionic equation (or half-equations) for the reaction of acidified manganate(vII) (permanganate) ions with iron(11) ions. (b) How many moles of iron(iI) ions react with one mole of MnO4 ions? (c) How many moles of Fe2 (d) How many grams of Fe2+ (Fe = 56) react with 25 cm of 0.04 M KMNO4(aq)? are there in the 200 cm of original solution? 3 (e) Calculate the % by mass of iron in the impure iron(11) salt.

Fe = 55.8; S = 32; O= 16; H 1 %3D 10 10g of an impure iron(11) salt were dissolved in water and made up to 200 cm of solution. 20cm of this solution; acidified with dilute sulphuric acid, required 25 cm of 0.04 M KMNO4(aq) before a faint pink colour appeared. (a) Write a balanced ionic equation (or half-equations) for the reaction of acidified manganate(vII) (permanganate) ions with iron(11) ions. (b) How many moles of iron(iI) ions react with one mole of MnO4 ions? (c) How many moles of Fe2 (d) How many grams of Fe2+ (Fe = 56) react with 25 cm of 0.04 M KMNO4(aq)? are there in the 200 cm of original solution? 3 (e) Calculate the % by mass of iron in the impure iron(11) salt.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter22: Bulk Electrolysis: Electrogravimetry And Coulometry

Section: Chapter Questions

Problem 22.21QAP

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