![\"\"](\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/03\/image-616.png\")
<\/figure>\n\n\n\nTo determine the value of ‘x’ in the formula (NH\u2084)\u2082SO\u2084\u00b7FeSO\u2084\u00b7xH\u2082O for hydrated ammonium iron(II) sulfate, we can utilize the results of a potassium permanganate (KMnO\u2084) titration. Here’s a step-by-step explanation:<\/p>\n\n\n\n
1. Understanding the Reaction:<\/strong><\/p>\n\n\n\n In acidic conditions, KMnO\u2084 reacts with Fe\u00b2\u207a ions according to the balanced equation:<\/p>\n\n\n\n [ \\text{MnO}_4^- (aq) + 5 \\, \\text{Fe}^{2+} (aq) + 8 \\, \\text{H}^+ (aq) \\rightarrow \\text{Mn}^{2+} (aq) + 5 \\, \\text{Fe}^{3+} (aq) + 4 \\, \\text{H}_2\\text{O} (l) ]<\/p>\n\n\n\n This equation indicates that one mole of MnO\u2084\u207b reacts with five moles of Fe\u00b2\u207a.<\/p>\n\n\n\n 2. Calculating Moles of KMnO\u2084 Used:<\/strong><\/p>\n\n\n\n The volume of KMnO\u2084 solution used in the titration is given as 2.250 mL (0.002250 L) with a concentration of 0.148 M. The moles of KMnO\u2084 reacted are:<\/p>\n\n\n\n [ \\text{Moles of KMnO}_4^- = 0.148 \\, \\text{mol\/L} \\times 0.002250 \\, \\text{L} = 0.000333 \\, \\text{mol} ]<\/p>\n\n\n\n 3. Determining Moles of Fe\u00b2\u207a in the Titrated Sample:<\/strong><\/p>\n\n\n\n Using the stoichiometric ratio from the balanced equation (1:5), the moles of Fe\u00b2\u207a in the 25.0 mL sample are:<\/p>\n\n\n\n [ \\text{Moles of Fe}^{2+} = 5 \\times 0.000333 \\, \\text{mol} = 0.001665 \\, \\text{mol} ]<\/p>\n\n\n\n 4. Extrapolating to the Total Moles of Fe\u00b2\u207a in the Original Solution:<\/strong><\/p>\n\n\n\n Since the 25.0 mL sample is one-tenth of the total 250.0 mL solution, the total moles of Fe\u00b2\u207a in the original solution are:<\/p>\n\n\n\n [ \\text{Total moles of Fe}^{2+} = 0.001665 \\, \\text{mol} \\times 10 = 0.01665 \\, \\text{mol} ]<\/p>\n\n\n\n 5. Calculating the Mass of Fe\u00b2\u207a in the Original Solution:<\/strong><\/p>\n\n\n\n The molar mass of Fe is approximately 55.85 g\/mol, so the mass of Fe\u00b2\u207a is:<\/p>\n\n\n\n [ \\text{Mass of Fe}^{2+} = 0.01665 \\, \\text{mol} \\times 55.85 \\, \\text{g\/mol} = 0.930 \\, \\text{g} ]<\/p>\n\n\n\n 6. Determining the Moles of Anhydrous Ammonium Iron(II) Sulfate:<\/strong><\/p>\n\n\n\n The total mass of the salt used is 8.325 g. The moles of the anhydrous salt (FeSO\u2084\u00b7(NH\u2084)\u2082SO\u2084) are:<\/p>\n\n\n\n [ \\text{Moles of salt} = \\frac{8.325 \\, \\text{g}}{394.2 \\, \\text{g\/mol}} = 0.02112 \\, \\text{mol} ]<\/p>\n\n\n\n 7. Calculating the Number of Moles of Water (x):<\/strong><\/p>\n\n\n\n The difference between the moles of Fe\u00b2\u207a and the moles of anhydrous salt corresponds to the moles of water of crystallization:<\/p>\n\n\n\n [ \\text{Moles of water} = 0.02112 \\, \\text{mol} – 0.01665 \\, \\text{mol} = 0.00447 \\, \\text{mol} ]<\/p>\n\n\n\n 8. Determining the Value of x:<\/strong><\/p>\n\n\n\n Each formula unit of the hydrated salt contains one Fe\u00b2\u207a ion. Therefore, the number of moles of water per mole of salt is:<\/p>\n\n\n\n [ x = \\frac{0.00447 \\, \\text{mol}}{0.02112 \\, \\text{mol}} \\times 100 = 21.2\\% ]<\/p>\n\n\n\n This percentage corresponds to approximately 2 water molecules per formula unit, suggesting that x \u2248 2.<\/p>\n\n\n\n Conclusion:<\/strong><\/p>\n\n\n\n Based on the titration data and calculations, the value of ‘x’ in the formula (NH\u2084)\u2082SO\u2084\u00b7FeSO\u2084\u00b7xH\u2082O is approximately 2, indicating that the hydrated salt contains 2 molecules of water of crystallization per formula unit.<\/p>\n","protected":false},"excerpt":{"rendered":" Hydrated ammonium iron (II) sulfate crystals have the formula (NH4)2SO4FeSO4 xH2O. 8.325 g (394.2g\/mol) of the salt were dissolved in 250.0 ml of acidified water. A 25.0 mL portion of this solution was titrated with potassium manganate (VII) solution of concentration 0.148 M. A volume of 2.250 mL was required. Calculate the value of x. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-198092","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/198092","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=198092"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/198092\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=198092"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=198092"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=198092"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}