{"id":1421,"date":"2026-05-12T21:47:48","date_gmt":"2026-05-12T21:47:48","guid":{"rendered":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/solution-exercise-21\/"},"modified":"2026-05-13T03:39:40","modified_gmt":"2026-05-13T03:39:40","slug":"solution-exercise-21","status":"publish","type":"chapter","link":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/solution-exercise-21\/","title":{"raw":"Solution Exercise 21","rendered":"Solution Exercise 21"},"content":{"raw":"
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\r\n
The sum of the cation milliequivalents (i.e., positively charged ions) is 7.79 meq\/L. The sum of the anion milliequivalents (i.e., negatively charged ions) is 7.56 meq\/L. The charge balance is calculated as:<\/blockquote>\r\n<\/div>\r\n
\r\n\r\n[latex]C.B. = \\frac{\\left( \\Sigma_{cations} - \\ \\Sigma_{anions} \\right)}{\\left( \\Sigma_{cations} + \\ \\Sigma_{anions} \\right)}(100)[\/latex]\r\n\r\n<\/div>\r\n
\r\n\r\n[latex]\\frac{\\left( 7.79\\frac{meq}{L} - 7.56\\frac{meq}{L} \\right)}{\\left( 7.79\\frac{meq}{L} + 7.56\\frac{meq}{L} \\right)}(100) = 0.0145(100) = 1.45\\%[\/latex]\r\n\r\n<\/div>\r\n
\r\n
The charge balance is less than 5% and is therefore an acceptable charge balance.<\/blockquote>\r\n<\/div>\r\n
\r\n\r\nReturn to Exercise 21<\/strong><\/span><\/a>\u2ba5\r\n\r\n<\/div>\r\n
\r\n\r\nReturn to where text linked to Exercise 21<\/strong><\/span><\/a>\u2ba5\r\n\r\n<\/div>\r\n<\/div>","rendered":"
\n
\n

The sum of the cation milliequivalents (i.e., positively charged ions) is 7.79 meq\/L. The sum of the anion milliequivalents (i.e., negatively charged ions) is 7.56 meq\/L. The charge balance is calculated as:<\/p><\/blockquote>\n<\/div>\n

\n

[latex]C.B. = \\frac{\\left( \\Sigma_{cations} - \\ \\Sigma_{anions} \\right)}{\\left( \\Sigma_{cations} + \\ \\Sigma_{anions} \\right)}(100)[\/latex]<\/p>\n<\/div>\n

\n

[latex]\\frac{\\left( 7.79\\frac{meq}{L} - 7.56\\frac{meq}{L} \\right)}{\\left( 7.79\\frac{meq}{L} + 7.56\\frac{meq}{L} \\right)}(100) = 0.0145(100) = 1.45\\%[\/latex]<\/p>\n<\/div>\n

\n

The charge balance is less than 5% and is therefore an acceptable charge balance.<\/p><\/blockquote>\n<\/div>\n

\n

Return to Exercise 21<\/strong><\/span><\/a>\u2ba5<\/p>\n<\/div>\n

\n

Return to where text linked to Exercise 21<\/strong><\/span><\/a>\u2ba5<\/p>\n<\/div>\n<\/div>\n","protected":false},"author":8,"menu_order":132,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-1421","chapter","type-chapter","status-publish","hentry"],"part":1531,"_links":{"self":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters\/1421","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/wp\/v2\/users\/8"}],"version-history":[{"count":2,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters\/1421\/revisions"}],"predecessor-version":[{"id":1839,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters\/1421\/revisions\/1839"}],"part":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/parts\/1531"}],"metadata":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters\/1421\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/wp\/v2\/media?parent=1421"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapter-type?post=1421"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/wp\/v2\/contributor?post=1421"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/wp\/v2\/license?post=1421"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}