{"id":256177,"date":"2025-07-14T04:44:40","date_gmt":"2025-07-14T04:44:40","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=256177"},"modified":"2025-07-14T04:44:42","modified_gmt":"2025-07-14T04:44:42","slug":"phosphate-po4-is-a-polyatomic-ion-that-can-combine-with-any-cation-to-form-an-ionic-compound","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/14\/phosphate-po4-is-a-polyatomic-ion-that-can-combine-with-any-cation-to-form-an-ionic-compound\/","title":{"rendered":"Phosphate; PO4- is a polyatomic ion that can combine with any cation to form an ionic compound."},"content":{"rendered":"\n

Phosphate; PO4- is a polyatomic ion that can combine with any cation to form an ionic compound. Identify all the formulas below that correctly represent phosphate compounds. Select one or more: Combined with magnesium: Mg3(PO4)2 Combined with iron(III): FePO4 Combined with magnesium: Mg(PO4)2 Combined with copper(II): Cu3(PO4)2 Combined with lithium: Li3PO4 Combined with iron(III): Fe3(PO4)2 Combined with copper(II): Cu3(PO4)2 Combined with lithium: Li3PO4<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

The correct formulas for phosphate compounds, based on the provided options, are:<\/p>\n\n\n\n

    \n
  1. Mg\u2083(PO\u2084)\u2082<\/strong> (Magnesium phosphate)<\/li>\n\n\n\n
  2. FePO\u2084<\/strong> (Iron(III) phosphate)<\/li>\n\n\n\n
  3. Cu\u2083(PO\u2084)\u2082<\/strong> (Copper(II) phosphate)<\/li>\n\n\n\n
  4. Li\u2083PO\u2084<\/strong> (Lithium phosphate)<\/li>\n<\/ol>\n\n\n\n

    Explanation:<\/h3>\n\n\n\n

    Phosphate is a polyatomic ion with the formula PO\u2084\u00b3\u207b<\/strong>. When phosphate combines with cations to form ionic compounds, the cation\u2019s charge must balance the charge of the phosphate ion.<\/p>\n\n\n\n

      \n
    1. Magnesium phosphate (Mg\u2083(PO\u2084)\u2082)<\/strong>:\n
        \n
      • Magnesium (Mg\u00b2\u207a) has a +2 charge. To balance the 3\u2212 charge of the phosphate ion, three magnesium ions are needed for every two phosphate ions. This gives the formula Mg\u2083(PO\u2084)\u2082<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
      • Iron(III) phosphate (FePO\u2084)<\/strong>:\n
          \n
        • Iron(III) (Fe\u00b3\u207a) has a +3 charge. To balance the 3\u2212 charge of the phosphate ion, one iron(III) ion is needed for every one phosphate ion. This results in the formula FePO\u2084<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
        • Copper(II) phosphate (Cu\u2083(PO\u2084)\u2082)<\/strong>:\n
            \n
          • Copper(II) (Cu\u00b2\u207a) has a +2 charge. To balance the 3\u2212 charge of the phosphate ion, three copper(II) ions are needed for every two phosphate ions. This gives the formula Cu\u2083(PO\u2084)\u2082<\/strong>.<\/li>\n<\/ul>\n<\/li>\n\n\n\n
          • Lithium phosphate (Li\u2083PO\u2084)<\/strong>:\n
              \n
            • Lithium (Li\u207a) has a +1 charge. To balance the 3\u2212 charge of the phosphate ion, three lithium ions are needed for every one phosphate ion. This results in the formula Li\u2083PO\u2084<\/strong>.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n

              Incorrect formulas:<\/h3>\n\n\n\n
                \n
              • Mg(PO\u2084)\u2082<\/strong> is incorrect because magnesium typically forms a 2+ charge and would need 3 phosphate ions to balance. This formula does not balance the charges correctly.<\/li>\n\n\n\n
              • Fe\u2083(PO\u2084)\u2082<\/strong> is incorrect for the same reason; it implies a different stoichiometry than the proper formula for iron(III) phosphate, which is FePO\u2084<\/strong>.<\/li>\n<\/ul>\n\n\n\n

                Thus, the correct formulas are Mg\u2083(PO\u2084)\u2082<\/strong>, FePO\u2084<\/strong>, Cu\u2083(PO\u2084)\u2082<\/strong>, and Li\u2083PO\u2084<\/strong>.<\/p>\n\n\n\n

                \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

                Phosphate; PO4- is a polyatomic ion that can combine with any cation to form an ionic compound. Identify all the formulas below that correctly represent phosphate compounds. Select one or more: Combined with magnesium: Mg3(PO4)2 Combined with iron(III): FePO4 Combined with magnesium: Mg(PO4)2 Combined with copper(II): Cu3(PO4)2 Combined with lithium: Li3PO4 Combined with iron(III): Fe3(PO4)2 […]<\/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-256177","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/256177","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=256177"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/256177\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=256177"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=256177"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=256177"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}