{"id":1424,"date":"2026-05-12T21:47:49","date_gmt":"2026-05-12T21:47:49","guid":{"rendered":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/solution-exercise-23\/"},"modified":"2026-05-13T03:39:53","modified_gmt":"2026-05-13T03:39:53","slug":"solution-exercise-23","status":"publish","type":"chapter","link":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/solution-exercise-23\/","title":{"raw":"Solution Exercise 23","rendered":"Solution Exercise 23"},"content":{"raw":"<div id=\"solution-exercise-23\" class=\"level1\">\r\n<div data-custom-style=\"First Paragraph\">\r\n\r\nCalculate the Piper Fractions:\r\n\r\n<\/div>\r\n<table style=\"width: 74%;\" data-custom-style=\"Table\"><colgroup> <col style=\"width: 15%;\" \/> <col style=\"width: 14%;\" \/> <col style=\"width: 30%;\" \/> <col style=\"width: 12%;\" \/> <\/colgroup>\r\n<tbody>\r\n<tr>\r\n<td style=\"text-align: center;\"><strong>Solutes<\/strong><\/td>\r\n<td style=\"text-align: center;\"><strong>meq\/L<\/strong><\/td>\r\n<td style=\"text-align: center;\" colspan=\"2\"><strong>Piper Fractions<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: left;\">[latex]{Ca}_{}^{2 +}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">4.59<\/td>\r\n<td style=\"text-align: right;\">4.59\/7.78 = 0.59(100) =<\/td>\r\n<td style=\"text-align: center;\"><strong>59%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: left;\">[latex]{Mg}_{}^{2 +}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">2.80<\/td>\r\n<td style=\"text-align: right;\">2.8\/7.78 = 0.36(100) =<\/td>\r\n<td style=\"text-align: center;\"><strong>36%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: left;\">[latex]{Na}_{}^{+}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">0.36<\/td>\r\n<td style=\"text-align: right;\" rowspan=\"2\">(0.36+0.04)\/7.78 = 0.05(100) =<\/td>\r\n<td style=\"text-align: center;\" rowspan=\"2\"><strong>5%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: left;\">[latex]K_{}^{+}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">0.04<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: right;\" colspan=\"2\"><strong>Sum cations:<\/strong><\/td>\r\n<td style=\"text-align: left;\"><strong>7.78 meq\/L<\/strong><\/td>\r\n<td style=\"text-align: center;\"><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: center;\">[latex]{HCO}_{3}^{-}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">5.33<\/td>\r\n<td style=\"text-align: right;\">5.33\/7.35 = 0.73(100) =<\/td>\r\n<td style=\"text-align: center;\"><strong>73%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: center;\">[latex]{SO}_{4}^{2 -}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">1.75<\/td>\r\n<td style=\"text-align: right;\">1.75\/7.35 = 0.24(100) =<\/td>\r\n<td style=\"text-align: center;\"><strong>24%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: center;\">[latex]{Cl}_{}^{-}[\/latex]<\/td>\r\n<td style=\"text-align: center;\">0.27<\/td>\r\n<td style=\"text-align: right;\">0.27\/7.35 = 0.04(100) =<\/td>\r\n<td style=\"text-align: center;\"><strong>4%<\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"text-align: right;\" colspan=\"2\"><strong>Sum anions:<\/strong><\/td>\r\n<td style=\"text-align: left;\"><strong>7.35 meq\/L<\/strong><\/td>\r\n<td style=\"text-align: center;\"><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<div data-custom-style=\"Body Text\">\r\n\r\n<img style=\"display: block; margin-left: auto; margin-right: auto; ;width: 4.4in; height: 3.8in;\" src=\"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-content\/uploads\/sites\/42\/2026\/05\/file171-2.jpg\" alt=\"A diagram of a triangle Description automatically generated\" \/>\r\n\r\n<\/div>\r\n<div data-custom-style=\"Block Text\">\r\n<blockquote>The water is a Calcium-Magnesium-Bicarbonate type as indicated in <a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/graphical-representations-of-geochemical-data\/#Xb98de44fac8a5185500a1e5515ff06d339b0a9c\"><span data-custom-style=\"Hyperlink\">Figure 82<\/span><\/a>. However, it is more appropriate to call it a Calcium-Bicarbonate water as Ca<sup>2+<\/sup> makes up more than 50% of all the cations.<\/blockquote>\r\n<\/div>\r\n<div data-custom-style=\"First Paragraph\">\r\n\r\n<a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/exercise-23\/#exercise-23\"><span data-custom-style=\"Hyperlink\"><strong>Return to Exercise 23<\/strong><\/span><\/a>\u2ba5\r\n\r\n<\/div>\r\n<div data-custom-style=\"Body Text\">\r\n\r\n<a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/graphical-representations-of-geochemical-data\/#extext23\"><span data-custom-style=\"Hyperlink\"><strong>Return to where text linked to Exercise 23<\/strong><\/span><\/a>\u2ba5\r\n\r\n<\/div>\r\n<\/div>","rendered":"<div id=\"solution-exercise-23\" class=\"level1\">\n<div data-custom-style=\"First Paragraph\">\n<p>Calculate the Piper Fractions:<\/p>\n<\/div>\n<table style=\"width: 74%;\" data-custom-style=\"Table\">\n<colgroup>\n<col style=\"width: 15%;\" \/>\n<col style=\"width: 14%;\" \/>\n<col style=\"width: 30%;\" \/>\n<col style=\"width: 12%;\" \/> <\/colgroup>\n<tbody>\n<tr>\n<td style=\"text-align: center;\"><strong>Solutes<\/strong><\/td>\n<td style=\"text-align: center;\"><strong>meq\/L<\/strong><\/td>\n<td style=\"text-align: center;\" colspan=\"2\"><strong>Piper Fractions<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\">[latex]{Ca}_{}^{2 +}[\/latex]<\/td>\n<td style=\"text-align: center;\">4.59<\/td>\n<td style=\"text-align: right;\">4.59\/7.78 = 0.59(100) =<\/td>\n<td style=\"text-align: center;\"><strong>59%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\">[latex]{Mg}_{}^{2 +}[\/latex]<\/td>\n<td style=\"text-align: center;\">2.80<\/td>\n<td style=\"text-align: right;\">2.8\/7.78 = 0.36(100) =<\/td>\n<td style=\"text-align: center;\"><strong>36%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\">[latex]{Na}_{}^{+}[\/latex]<\/td>\n<td style=\"text-align: center;\">0.36<\/td>\n<td style=\"text-align: right;\" rowspan=\"2\">(0.36+0.04)\/7.78 = 0.05(100) =<\/td>\n<td style=\"text-align: center;\" rowspan=\"2\"><strong>5%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: left;\">[latex]K_{}^{+}[\/latex]<\/td>\n<td style=\"text-align: center;\">0.04<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: right;\" colspan=\"2\"><strong>Sum cations:<\/strong><\/td>\n<td style=\"text-align: left;\"><strong>7.78 meq\/L<\/strong><\/td>\n<td style=\"text-align: center;\"><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">[latex]{HCO}_{3}^{-}[\/latex]<\/td>\n<td style=\"text-align: center;\">5.33<\/td>\n<td style=\"text-align: right;\">5.33\/7.35 = 0.73(100) =<\/td>\n<td style=\"text-align: center;\"><strong>73%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">[latex]{SO}_{4}^{2 -}[\/latex]<\/td>\n<td style=\"text-align: center;\">1.75<\/td>\n<td style=\"text-align: right;\">1.75\/7.35 = 0.24(100) =<\/td>\n<td style=\"text-align: center;\"><strong>24%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">[latex]{Cl}_{}^{-}[\/latex]<\/td>\n<td style=\"text-align: center;\">0.27<\/td>\n<td style=\"text-align: right;\">0.27\/7.35 = 0.04(100) =<\/td>\n<td style=\"text-align: center;\"><strong>4%<\/strong><\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: right;\" colspan=\"2\"><strong>Sum anions:<\/strong><\/td>\n<td style=\"text-align: left;\"><strong>7.35 meq\/L<\/strong><\/td>\n<td style=\"text-align: center;\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div data-custom-style=\"Body Text\">\n<p><img decoding=\"async\" style=\"display: block; margin-left: auto; margin-right: auto; ;width: 4.4in; height: 3.8in;\" src=\"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-content\/uploads\/sites\/42\/2026\/05\/file171-2.jpg\" alt=\"A diagram of a triangle Description automatically generated\" \/><\/p>\n<\/div>\n<div data-custom-style=\"Block Text\">\n<blockquote><p>The water is a Calcium-Magnesium-Bicarbonate type as indicated in <a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/graphical-representations-of-geochemical-data\/#Xb98de44fac8a5185500a1e5515ff06d339b0a9c\"><span data-custom-style=\"Hyperlink\">Figure 82<\/span><\/a>. However, it is more appropriate to call it a Calcium-Bicarbonate water as Ca<sup>2+<\/sup> makes up more than 50% of all the cations.<\/p><\/blockquote>\n<\/div>\n<div data-custom-style=\"First Paragraph\">\n<p><a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/exercise-23\/#exercise-23\"><span data-custom-style=\"Hyperlink\"><strong>Return to Exercise 23<\/strong><\/span><\/a>\u2ba5<\/p>\n<\/div>\n<div data-custom-style=\"Body Text\">\n<p><a href=\"\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/chapter\/graphical-representations-of-geochemical-data\/#extext23\"><span data-custom-style=\"Hyperlink\"><strong>Return to where text linked to Exercise 23<\/strong><\/span><\/a>\u2ba5<\/p>\n<\/div>\n<\/div>\n","protected":false},"author":8,"menu_order":134,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-1424","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\/1424","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\/1424\/revisions"}],"predecessor-version":[{"id":1841,"href":"https:\/\/books.gw-project.org\/basic-hydrogeology-an-introduction-to-the-fundamentals-of-groundwater-science\/wp-json\/pressbooks\/v2\/chapters\/1424\/revisions\/1841"}],"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\/1424\/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=1424"}],"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=1424"},{"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=1424"},{"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=1424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}