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<title>DP Chemistry: Index of Hydrogen Deficiency (IHD)</title>
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auxiliary case study</a></li><li><a href="../../page/19258/nuclear-medicine-.html">Nuclear medicine </a></li><li><a href="../../page/19273/drug-detection-analysis-.html">Drug detection & analysis </a></li></ul></li></ul></li><li><a href="../../page/16592/practical-scheme-of-work-ia-.html">Practical scheme of work & IA </a><ul class="level-1"><li><a href="../../page/16682/internal-assessment.html" class="father">Internal Assessment</a><ul class="level-2"><li><a href="../../page/18892/scaffolding-the-investigation.html">'Scaffolding' the investigation</a></li><li><a href="../../page/18896/timing-organisation-.html">Timing & organisation </a></li><li><a href="../../page/18905/choosing-the-research-question.html">Choosing the research question</a></li><li><a href="../../page/18946/personal-engagement.html">Personal engagement</a></li><li><a href="../../page/18950/exploration.html">Exploration</a></li><li><a href="../../page/18957/analysis.html">Analysis</a></li><li><a href="../../page/18965/evaluation.html">Evaluation</a></li><li><a href="../../page/18966/communication.html">Communication</a></li><li><a href="../../page/19882/internal-standardization-of-the-ia.html">Internal standardization of the IA</a></li><li><a href="../../page/19901/submitting-the-samples-for-moderation.html">Submitting the samples for moderation</a></li><li><a href="../../page/33754/ten-suggestions-for-ias-using-secondary-data.html">Ten suggestions for IAs using secondary data</a></li><li><a href="../../page/37544/gaining-full-marks-for-a-databased-ia-.html">Gaining full marks for a databased IA </a></li><li><a href="../../page/19506/ia-example-marking-exercise-.html">IA example & marking exercise </a></li><li><a href="../../page/23929/genuine-examples-of-moderated-ia-reports.html">Genuine examples of moderated IA reports</a></li><li><a href="../../page/25234/examples-of-teacher-marked-ia-reports-.html">Examples of teacher-marked IA reports </a></li><li><a href="../../page/37542/history-of-internal-assessment.html">History of Internal Assessment</a></li></ul></li><li><a href="../../page/16598/mandatory-laboratory-components.html" class="father">Mandatory laboratory components</a><ul class="level-2"><li><a href="../../page/16613/formula-of-magnesium-oxide-.html">Formula of magnesium oxide </a></li><li><a href="../../page/16612/determining-the-mr-of-an-unknown-gas.html">Determining the <i>M</i><sub>r</sub> of an unknown gas</a></li><li><a href="../../page/16615/acid-base-titrations-.html">Acid-base titrations </a></li><li><a href="../../page/16616/a-green-acid-base-practical.html">A green acid-base practical</a></li><li><a href="../../page/16617/analysis-of-aspirin-tablets.html">Analysis of aspirin tablets</a></li><li><a href="../../page/16618/caco3-in-egg-shells.html">CaCO<sub>3</sub> in egg shells</a></li><li><a href="../../page/16644/enthalpy-changes.html">Enthalpy changes</a></li><li><a href="../../page/16631/reaction-rates.html">Reaction rates</a></li><li><a href="../../page/16635/rate-dependent-factors.html">Rate-dependent factors</a></li><li><a href="../../page/16636/determining-ea-for-a-reaction.html">Determining <i>E</i><sub>a</sub> for a reaction</a></li><li><a href="../../page/16637/iodination-of-propanone.html">Iodination of propanone</a></li><li><a href="../../page/18144/titrations-with-a-ph-meter.html">Titrations with a pH meter</a></li><li><a href="../../page/18355/redox-titration-with-kmno4-.html">Redox titration with KMnO<sub>4</sub> </a></li><li><a href="../../page/16640/voltaic-cells.html">Voltaic cells</a></li><li><a href="../../page/16659/3-d-molecular-modelling-.html">3-D molecular modelling </a></li></ul></li><li><a href="../../page/17168/other-good-practicals.html" class="father">Other good practicals</a><ul class="level-2"><li><a href="../../page/17196/common-chemical-reactions.html">Common chemical reactions</a></li><li><a href="../../page/227/elements-oxides-of-the-third-period-.html">Elements & oxides of the third period </a></li><li><a href="../../page/17239/the-halogens.html">The halogens</a></li><li><a href="../../page/17162/boiling-points-of-mixtures.html">Boiling points of mixtures</a></li><li><a href="../../page/17170/polarity-of-molecules.html">Polarity of molecules</a></li><li><a href="../../page/18083/le-chateliers-principle-.html">Le Chatelier's principle </a></li><li><a href="../../page/19582/determining-kc-for-an-esterification-reaction.html">Determining <i>K</i><sub>c</sub> for an esterification reaction</a></li><li><a href="../../page/18164/redox-reactions-of-vanadium-.html">Redox reactions of vanadium </a></li><li><a href="../../page/18351/chlorine-in-swimming-pools-.html">Chlorine in swimming pools </a></li><li><a href="../../page/18178/analysis-of-cuii-ions-in-solution-.html">Analysis of Cu(II) ions in solution </a></li><li><a href="../../page/18179/percentage-of-copper-in-brass.html">Percentage of copper in brass</a></li><li><a href="../../page/18356/electrolytic-cells-.html">Electrolytic cells </a></li><li><a href="../../page/18598/reactions-of-organic-compounds.html">Reactions of organic compounds</a></li><li><a href="../../page/18752/hydrolysis-of-halogenoalkanes.html">Hydrolysis of halogenoalkanes</a></li><li><a href="../../page/18784/preparation-of-13-dinitrobenzene-.html">Preparation of 1,3-dinitrobenzene </a></li><li><a href="../../page/19022/determination-of-an-organic-structure.html">Determination of an organic structure</a></li><li><a href="../../page/19887/preparation-of-nylon-66.html">Preparation of nylon 6,6</a></li><li><a href="../../page/19343/determination-of-vitamin-c-content-.html">Determination of vitamin C content </a></li><li><a href="../../page/19342/hydrolysis-of-starch-.html">Hydrolysis of starch </a></li><li><a href="../../page/19159/preparation-purification-of-aspirin-.html">Preparation & purification of aspirin </a></li></ul></li><li><a href="../../page/18851/ict-in-practical-work.html" class="father">ICT in practical work</a><ul class="level-2"><li><a href="../../page/18852/data-logging-.html">Data logging </a></li><li><a href="../../page/18853/software-for-graph-plotting-.html">Software for graph plotting </a></li><li><a href="../../page/18854/spreadsheets-for-data-processing-.html">Spreadsheets for data processing </a></li><li><a href="../../page/18855/databases.html">Databases</a></li><li><a href="../../page/18856/computer-modelling-simulations-.html">Computer modelling & simulations </a></li></ul></li><li><a href="../../page/16594/group-4-project.html" class="father">Group 4 Project</a><ul class="level-2"><li><a href="../../page/16595/practicalities.html">Practicalities</a></li><li><a href="../../page/16596/reflective-statement-.html">Reflective statement </a></li></ul></li><li><a 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</a></li><li><a href="../../page/17787/hl-questions-on-each-sub-topic-.html">HL Questions on each sub-topic </a></li><li><a href="../../page/20428/hl-paper-3-section-a-questions.html">HL Paper 3 Section A questions</a></li><li><a href="../../page/17793/hl-questions-on-the-options.html">HL Questions on the options</a></li><li><a href="../../page/24973/hl-quizzes-on-option-sub-topics.html">HL Quizzes on option sub-topics</a></li><li><a href="../../page/41573/printable-versions-of-written-tasks-.html">Printable versions of written tasks </a></li></ul></li><li><a href="../../page/41465/complete-course-for-students-.html">Complete course for students </a><ul class="level-1"><li><a href="../../page/27988/full-coverage-of-each-topic-and-sub-topic.html" class="father">Full coverage of each topic and sub-topic</a><ul class="level-2"><li><a href="../../page/27959/topic-1-stoichiometric-relationships.html">Topic 1 : Stoichiometric relationships</a></li><li><a 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<h1 class="section-title">Index of Hydrogen Deficiency (IHD)</h1>
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Saturday 12 March 2016
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<div style="padding: 0 30px;"><p>The Index of Hydrogen Deficiency applies to organic compounds and is part of sub-topic <a href="../../page/18968/spectroscopic-identification-of-organic-compounds.html" title="Core & AHL » Teaching each topic & sub-topic » Topics 11 & 21 » Spectroscopic identification of organic compounds">11.3 Spectroscopic identification of organic compounds</a> in the IB programme. Most books and websites that deal with this give a formula which can be applied, for example IHD = ½ x (2<em>x</em> + 2 - <em>y</em>) where <em>x</em> = the number of carbon atoms and <em>y</em> = the number of hydrogen atoms. However in an exam students may well not remember this or may apply it incorrectly, particularly when atoms other than C and H are involved, so it seems much better to me if they can always work it out from first principles which avoids the use of any formula. This is particularly relevant as the specimen papers have the wrong answer to a question that asks for the IHD of C<sub>19</sub>H<sub>20</sub>N<sub>2</sub>O<sub>2</sub>.</p>
<p>The Index of Hydrogen Deficiency used to be known as the degree of unsaturation. In many ways it would be better if the shortened version was IH<sub>2</sub>D rather than IHD as it is equal to the number of units of H<sub>2</sub> that need to be added to make the organic compound in question fully saturated. To work out the IHD all that needs to be known is the molecular formula of the compound.</p>
<p>For hydrocarbons just calculate the number of units of H<sub>2</sub> that need to be added to make it into an alkane, i.e. to give it the formula C<sub>n</sub>H<sub>(2n+2)</sub>. Thus C<sub>6</sub>H<sub>12</sub> has an IHD of one. Note that all isomers of the same compound have the same IHD so whether C<sub>6</sub>H<sub>12</sub> refers to an alkene (e.g. hex-1-ene or hex-2-ene) or to a cyclic compound (e.g. cyclohexane or methylcyclopentane) makes no difference to the IHD.</p>
<p>If elements other than carbon and hydrogen are present then it depends upon which group in the periodic table they come from. In each case, rather than just remembering what to do without any understanding, it can be useful to work it out simply by substituting the element into a simple compound such as ethane.</p>
<p>Group 17 (F, Cl, Br, I). In chloroethane each carbon atom is surrounded by four single bonds so for any halogen just exchange the halogen atom for a hydrogen atom so that C<sub>2</sub>H<sub>5</sub>Cl becomes C<sub>2</sub>H<sub>6</sub> with an IHD or zero and C<sub>2</sub>H<sub>2</sub>Br<sub>2</sub> becomes C<sub>2</sub>H<sub>4 </sub>with an IHD of 1.</p>
<p>Group 16 (O, S). In ethanol the two carbon atoms still have four single bonds so the insertion of an oxygen atom into ethane to make either ethanol or methoxymethane has no effect on the IHD so oxygen atoms can simply be ignored when calculating the IHD. For example C<sub>2</sub>H<sub>6</sub>O becomes C<sub>2</sub>H<sub>6</sub> with an IHD of zero and C<sub>3</sub>H<sub>6</sub>O becomes C<sub>3</sub>H<sub>6</sub> with an IHD of 1.</p>
<p>Group 15 (N, P). Adding amine groups to a compound will not alter the IHD . Consider dimethylamine, (CH<sub>3</sub>)<sub>2</sub>NH, which is saturated. To calculate the IHD <strong>either</strong> remove all the nitrogen atoms and deduct one hydrogen atom for each nitrogen removed so that (CH<sub>3</sub>)<sub>2</sub>NH becomes C<sub>2</sub>H<sub>6</sub> with an IHD of zero, <strong>or</strong> change the nitrogen atoms into carbon atoms and add one hydrogen atom for each nitrogen atom changed so that (CH<sub>3</sub>)<sub>2</sub>NH becomes C<sub>3</sub>H<sub>8</sub> which of course also has an IHD of zero.</p>
<hr class="hidden">
<p>Now to apply the theory to two real examples.</p>
<p>1. A topical example is mildronate, otherwise known as meldonium, which the tennis player Maria Sharapova has admitted to using.</p>
<p style="text-align: center;"><img alt="" src="../../../ib/chemistry/images/2014-blog/maria-sharapova-1.jpg" style="width: 342px; height: 229px;"> <img alt="" src="../../../ib/chemistry/images/2014-blog/mildronate.jpg" style="width: 302px; height: 229px;"></p>
<p style="text-align: center;">Maria Sharapova (Image from Pavel Golovkin/Associated Press) and Mildronate mIB Docs (2) Teamfactured by Grindex</p>
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<p>Mildronate has the molecular formula C<sub>6</sub>H<sub>14</sub>N<sub>2</sub>O<sub>2</sub>. You should be able to calculate that the IHD is 1. This single degree of unsaturation is due to the carbonyl C=O bond in the molecule.</p>
<p>2. Now for the IB. Look at question Qu. 4(b)(iii) on the SL Paper 2 specimen paper (which is the same as Question 7(b)(iii) on the HL Paper 2). The molecular formula is C<sub>19</sub>H<sub>20</sub>N<sub>2</sub>O<sub>2</sub>. Removing the oxygen atoms gives C<sub>19</sub>H<sub>20</sub>N<sub>2</sub> and then removing the two N atoms and also deducting two hydrogen atoms gives C<sub>19</sub>H<sub>18</sub>. The saturated hydrocarbon containing 19 carbon atoms has 40 hydrogen atoms (C<sub>19</sub>H<sub>40</sub>) so we need to add 11 units of H<sub>2</sub> making the IHD 11. (Note that if you change the N atoms into C atoms and add one hydrogen for each N atom changed you get C<sub>21</sub>H<sub>22</sub> which also give an IHD of 11). 11 is the correct answer although currently the IB markscheme uses an unexplained formula wrongly to give 9.</p>
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l=$(this).width()+submenuW;$(this).css("margin-left","-"+l+"px"),$(this).addClass("fixed")}})))})),$("a.showhider").click((function(e){e.preventDefault();var box="#"+$(this).attr("rel"),show='<i class="fa fa-eye"></i>',hide='<i class="fa fa-eye-slash"></i>';$(box).slideToggle("fast"),$(this).html($(this).html()==show?hide:show),$(this).attr("title","Show"==$(this).attr("title")?"Hide":"Show")})),$("a.scroll-to").click((function(e){e.preventDefault();var n=$("#"+$(this).data("target")).offset().top-70;$("html, body").animate({scrollTop:n},300)})),$("a.print-section-blog").click((function(e){e.preventDefault(),printSectionBlog()})),$(".print-button").click((function(e){var target;e.preventDefault(),PopupPrint("#"+$(this).data("target-id"))})),$(".alert.alert-success").delay(6e3).hide("fast",fixDiv());var fancyParent=1==$("body").find($("#main-article")).length?"#main-article":"body",fancyOptions={loop:!1,openEffect:"elastic",closeEffect:"elastic",nextEffect:"fade",prevEffect:"fade",parent:fancyParent,helpers:{title:{type:"inside"}}};if($("ul.gallery").each((function(){var rel=$(this).find("li:first-child > a:first-child").attr("rel");$('ul.gallery a.fancy[rel="'+rel+'"]').fancybox(fancyOptions)})),$(".carousel.slide").each((function(){var rel="gallery-"+$(this).data("id");$('.carousel.slide a.fancy[rel="'+rel+'"]').fancybox(fancyOptions)})),$("img.pop").parent("a").each((function(){$(this).attr("title",$(this).children("img").attr("alt"))})),$("img.pop").parent("a").fancybox({loop:!1,helpers:{title:{type:"inside"}}}),!are_cookies_enabled()){var msg='<div class="alert alert-error"><i class="fa fa-warning"></i> Your browser does not accept cookies from this site. Please enable cookies to log in.</div><div class="alert alert-info"><i class="fa fa-question-circle"></i> Enabling cookies in <a target="_blank" style="margin: 0; padding: 0;" href="https://support.mozilla.org/en-US/kb/enable-and-disable-cookies-website-preferences">Firefox</a>, <a target="_blank" style="margin: 0; padding: 0;" href="https://support.google.com/accounts/answer/61416?hl=en">Chrome</a>, <a target="_blank" style="margin: 0; padding: 0;" href="http://windows.microsoft.com/en-us/windows-vista/block-or-allow-cookies">Explorer</a></div>';$("#modal-login .modal-header").append(msg)}if($(".panel-expandable > .panel-heading").click((function(e){e.preventDefault();var panel=$(this).closest(".panel-expandable"),expandables=panel.hasClass("panel-has-footer")?".panel-body, .panel-footer":".panel-body";panel.find(".panel-body").is(":visible")?(panel.find(expandables).slideUp("fast"),panel.find(".expander > .fa-minus").removeClass("fa-minus").addClass("fa-plus")):(panel.find(expandables).slideDown("fast"),panel.find(".expander > .fa-plus").removeClass("fa-plus").addClass("fa-minus"))})),$("#modal-find-out-more").css({width:.8*$("#container").width()+"px","margin-left":-.4*$("#container").width()+"px"}),$(".modal-xxl").length){var modalTopPos=Math.round(.07*$(window).height());$(window).width()>1200&&$(".modal-xxl").css({"max-width":$(window).width()>960?"960px":$(window).width()+"px",width:$(window).width()>960?"960px":$(window).width()+"px","margin-left":$(window).width()>960?"-480px":Math.round($(window).width()/2)}),$(".modal-xxl").css("top",modalTopPos+"px"),$(".modal-xxl").on("shown",(function(){var mHeaderH=$(this).find(".modal-header").outerHeight(),mBody=$(this).find(".modal-body"),mBodyH=mBody.outerHeight(),mFooterH=$(this).find(".modal-footer").outerHeight(),bottomOfTheModal=modalTopPos+mHeaderH+mBodyH+mFooterH;if(bottomOfTheModal<$(window).height())mBodyH+=$(window).height()-bottomOfTheModal-60,mBody.css("max-height",mBodyH+"px");else{$(window).scrollTop(0),modalTopPos=10,$(".modal-xxl").css("top",modalTopPos+"px"),bottomOfTheModal=modalTopPos+mHeaderH+mBodyH+mFooterH,availableScroll=bottomOfTheModal-$(window).height()+modalTopPos;var lastPos=-1;$(window).on("scroll",(function(){var s=$(window).scrollTop()>availableScroll?availableScroll:$(window).scrollTop();newPos=modalTopPos-s,newPos!=lastPos&&($(".modal-xxl").css("top",newPos+"px"),lastPos=newPos)}))}}))}function popupHelp(url,title,w,h){var dualScreenLeft=void 0!==window.screenLeft?window.screenLeft:screen.left,dualScreenTop=void 0!==window.screenTop?window.screenTop:screen.top,width,height,left=(window.innerWidth?window.innerWidth:document.documentElement.clientWidth?document.documentElement.clientWidth:screen.width)/2-w/2+dualScreenLeft,top=(window.innerHeight?window.innerHeight:document.documentElement.clientHeight?document.documentElement.clientHeight:screen.height)/2-h/2+dualScreenTop,newWindow=window.open(url,title,"menubar=no,location=no,resizable=0, width="+w+", height="+h+", top="+top+", left="+left);return window.focus&&(newWindow?newWindow.focus():$('<div class="alert alert-warning" style="margin-bottom: 0px;"><p class="help-block">Pop Up blocked. Please allow Pop Ups in your browser settings.</p></div>').insertBefore("body")),newWindow}if($(".open-student-access-help").click((function(e){e.preventDefault();var h=$(window).height()-20,w=$(window).width()<1280?$(window).width():1280;popupHelp(helpURL,"Student Access Help",w,h)})),$(".pop-up-help").click((function(e){e.preventDefault();var url=$(this).attr("href"),title=$(this).data("title"),h=$(window).height()-20,w;popupHelp(url,title,$(window).width()<1280?$(window).width():1280,h)})),$("section.tib-hiddenbox").length){var count=0;$($("section.tib-hiddenbox").get().reverse()).each((function(){var box=$(this),revealButton;$("<a />").attr("class","btn showhider").attr("rel","hiddenBoxContent"+count).attr("style","margin-bottom: 0;").html('<i class="fa fa-eye"></i>').insertBefore(box);var newContainer=$("<div />").attr("class","hidden-content").attr("id","hiddenBoxContent"+count).html(box.html());newContainer.hide(),newContainer.insertBefore(box),box.remove(),count++})),$("a.showhider").on("click",(function(e){var container=$("#"+$(this).attr("rel"));container.is(":hidden")?(container.fadeIn("fast"),$(this).html('<i class="fa fa-eye-slash"></i>')):(container.fadeOut("fast"),$(this).html('<i class="fa fa-eye"></i>'))}))}
let commentEditor={};function initCommentsEditor(){const t=document.querySelector("#comment-content");t&&CKEDITOR.BasicEditor.create(t,{toolbar:{viewportTopOffset:50,items:["bold","italic","link","subscript","superscript"]},link:{decorators:{addLinkNoFollow:{mode:"automatic",callback:function(t){if(null!=t)return["http://","http://www","https://","https://www","ftp:"].some((o=>t.startsWith(o)))},attributes:{target:"_blank",class:"ck-link",rel:"nofollow"}}}}}).then((function(t){commentEditor=t,commentEditor.execute("heading",{value:"paragraph"})})).catch((function(t){console.error(t)}))}function replaceComment(content,commentId){$("#cancel-comment-post").trigger("click"),$("#comm-"+commentId+" > .comment-content div.comment-text").html(content)}function placeComment(html,fatherId){$("#comment-form").hide(),$("#comment-form textarea").val(""),fatherId>0?($("#comments #comm-"+fatherId).append(html),$("#comments").append($("#comment-form"))):$("#comments").append(html).append($("#comment-form")),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content").removeClass("marked"),$("#comment-form").show("fast")}function update_sticky_comments(arrIds,mode){$.post("pages/edit/update-sticky-comments.php?mode="+mode,{ids:arrIds,ticket:$("#comment-ticket").val()},(function(data){1==data.success?("set"==data.mode&&$("#sticky-"+data.id).parents("div.comment").each((function(e){$(this).find("a.pull-right").first().addClass("sticky"),$(this).find("a.pull-right").first().attr("title","Unmark as important")})),"unset"==data.mode&&($("#sticky-"+data.id).removeClass("sticky"),$("#sticky-"+data.id).attr("title","Mark as important"),$("#sticky-"+data.id).closest("div.comment").find("div.comment").each((function(e){$(this).find("a.pull-right").first().removeClass("sticky"),$(this).find("a.pull-right").first().attr("title","Mark as important")})))):alert(data.error)}),"json")}"undefined"!=typeof CKEDITOR&&initCommentsEditor(),$("section#comments").on("click","#edit-comment",(function(e){e.preventDefault();var commentId=$("form#comment-form #comment-mode").val(),commentContent=commentEditor.getData(),ticket=$("#comment-ticket").val(),sectionId=$("#section-id").val();$.post("pages/comment.php",{action:"edit",comment_id:commentId,content:commentContent,ticket:ticket},(function(data){"0"==data.success?alert(data.error):replaceComment(data.text,commentId)}),"json")})),$("section#comments").on("click","a.edit-comment",(function(e){e.preventDefault(),$(".comment .hidden").removeClass("hidden");var commentId=$(this).data("comment-id"),form=$("form#comment-form"),text=$("#comm-"+commentId+" > .comment-content div.comment-text").html();commentEditor.setData(text),$("form#comment-form textarea").val(""),$("form#comment-form textarea").val(text),$("#comm-"+commentId+" > .comment-content > img").addClass("hidden"),$("#comm-"+commentId+" > .comment-content > div.comment-text").addClass("hidden"),$("#comm-"+commentId+" > .comment-footer").addClass("hidden"),$("#comm-"+commentId+" > .comment-content").append(form),$("form#comment-form #submit-comment").hide(),$("form#comment-form #edit-comment").show(),$("form#comment-form #cancel-comment-post").show(),$("form#comment-form #comment-mode").val(commentId),fancyScrollTo("comment-form"),$("form#comment-form textarea").focus()})),$("section#comments").on("click","#submit-comment",(function(e){e.preventDefault();var commentContent=commentEditor.getData(),fatherId=$("#father-comment").val(),ticket=$("#comment-ticket").val(),sectionId=$("#section-id").val();$.post("pages/comment.php",{action:"post",section_id:sectionId,father_id:fatherId,content:commentContent,ticket:ticket},(function(data){if("0"==data.success)alert(data.error);else{commentEditor.setData(""),placeComment(data.html,fatherId),$("form#comment-form #cancel-comment-post").hide();var n=0;$("#n-comments").text().length>0&&(n=parseInt($("#n-comments").text())),$("#n-comments").text(n+1)}}),"json")})),$("section#comments").on("click","a.reply-comment",(function(e){e.preventDefault(),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content").removeClass("marked");var form=$("form#comment-form"),fatherId=$(this).parent().parent(".comment").attr("rel");form.find("#father-comment").val(fatherId),$(this).parent().parent(".comment").find("> .reply-area").append(form),$(this).find(".fa-reply").removeClass("fa-reply").addClass("fa-arrow-down"),$(this).parent().prev(".comment-content").addClass("marked"),$("form#comment-form #cancel-comment-post").show(),fancyScrollTo("comment-form"),$("form#comment-form textarea").focus()})),$("section#comments").on("click","#cancel-comment-post",(function(e){e.preventDefault(),$(".comment .hidden").removeClass("hidden"),$(".comment .fa-arrow-down").removeClass("fa-arrow-down").addClass("fa-reply"),$(".comment-content.marked").removeClass("marked"),commentEditor.setData("");var form=$("form#comment-form");$("section#comments").append(form),$("form#comment-form #father-comment").val("0"),$("form#comment-form textarea").val(""),$("form#comment-form #comment-mode").val("new"),$("#edit-comment").hide(),$(this).hide(),$("#submit-comment").show()})),$("section#comments").on("click","a.delete-comment",(function(e){var commentId=$(this).data("comment-id"),isFather=$("#comm-"+commentId).children(".comment").length>0,ticket=$("#comment-ticket").val(),msg="You are going to delete a comment.\n\nThis action cannot be undone.\n\nAre you sure?";isFather&&(msg="You are going to delete a comment and all its replies.\n\nThis action cannot be undone.\n\nAre you sure?"),confirm(msg)&&$.post("pages/comment.php",{action:"delete",comment_id:commentId,is_father:isFather,ticket:ticket},(function(data){if("0"==data.success)alert(data.error);else{$("#comm-"+commentId+".comment").replaceWith(data.text);var n=0;$("#n-comments").text().length&&(n=parseInt($("#n-comments").text())),$("#n-comments").text(n-parseInt(data.deleted))}}),"json"),e.preventDefault(),e.stopPropagation()})),$("section#comments").on("click","a.pull-right",(function(e){e.preventDefault();var arrayIds=[];$(this).hasClass("sticky")?(arrayIds.push($(this).closest("div.comment").attr("rel")),$(this).closest("div.comment").find("div.comment").each((function(e){arrayIds.push($(this).attr("rel"))})),update_sticky_comments(arrayIds,"unset")):($(this).parents("div.comment").each((function(e){arrayIds.push($(this).attr("rel"))})),update_sticky_comments(arrayIds,"set"))}));
$('.page-bookmarker').click(function(e){
e.preventDefault();
var pid = $(this).data('pid');
var random = $(this).data('ticket');
bookmarkPage(pid, random);
});
function bookmarkPage(pageId, random){
$.get(
'pages/bookmarks.php',
{
'id' : pageId,
'ticket' : random
},
function(data){
if(data['success'] == '1') {
var buttonTitle = 'Favourite';
if( $('.page-bookmarker').attr('title') == 'Favourite' ) {
buttonTitle = 'Unfavourite';
}
$('.page-bookmarker > i').toggleClass('colored');
$('.page-bookmarker.stacked > span').text(buttonTitle);
$('.page-bookmarker').attr('title', buttonTitle);
}
},
'json'
);
}
// the comment icon becomes a popover
$('img.ico[src="/img/icons/comments.png"]').each(function(){
var comment = $(this).attr('title');
$(this).removeAttr('title');
$(this).wrap('<a class="tib-popover" href="#" data-content="'+comment+'" data-togle="popover" data-placement="top" />');
});
$('img.ico[src="img/icons/comments.png"]').each(function(){
var comment = $(this).attr('title');
$(this).removeAttr('title');
$(this).wrap('<a class="tib-popover" href="#" data-content="'+comment+'" data-togle="popover" data-placement="top" />');
});
$('.tib-popover').popover({
html : true,
trigger : 'hover',
delay : {show: 300, hide: 300},
placement : function (context, source) {
var position = $(source).position();
if (position.top > 200) { return "top";}
if (position.left < 515) { return "right"; }
if (position.top < 200) { return "bottom";}
if (position.left > 515) { return "left"; }
return "top";
}
}).click(function(e){
e.preventDefault();
});
// LIVE CAROUSEL MANAGEMENT
// Miliseconds for the next slide
var carouselTime = 6500;
// Start carousels
$('div.carousel.slide').carousel({interval: carouselTime});
$('.tib-indicators > img').click(function(){
// IN
var index = $(this).index();
var container = $(this).closest('.carousel.slide');
container.carousel(index);
});
$('a.btn.showhider').click(function(e) {
var showHiderId = $( this ).attr('rel');
if ( $('#'+showHiderId).find('iframe').length > 0 ) {
$('#'+showHiderId+' iframe').each(function() {
if ( $(this).attr('src').indexOf('.pdf') > 0 ) {
this.contentWindow.location.reload(true);
}
});
}
});
var hTopmenu = $('#topmenu').height();
var n = 0;
$('nav.top-nav > ul > li').each(function(k, e) {
if (n > 1) {
var diff = hTopmenu-(e.offsetTop+e.offsetHeight);
$(e).find(' > ul ').css('margin-top', '-'+diff+'px');
}
n++;
});
});
</script>
</body>
</html>