CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie<\/title>\n<style>\n:root{\n --bg:#f5f7fb; --ink:#172033; --muted:#5c667a;\n --red:#b83227; --blue:#2457c5; --teal:#087f8c; --green:#2f855a; --violet:#6b46c1; --amber:#b7791f;\n --card:#ffffff; --line:#d6deeb; --soft-blue:#edf4ff; --soft-red:#fff2f0; --soft-green:#effaf5; --soft-violet:#f6f1ff;\n}\n*{box-sizing:border-box}\nbody{margin:0;background:radial-gradient(circle at 10% 0%,#eaf2ff 0,#f7f8fb 32%,#fff 100%);color:var(--ink);font-family:system-ui,-apple-system,BlinkMacSystemFont,\"Segoe UI\",sans-serif;line-height:1.56}\n.wrapper{max-width:1120px;margin:auto;padding:22px}\n.hero{background:linear-gradient(135deg,#ffffff 0%,#eef6ff 42%,#fff5ef 100%);border:1px solid var(--line);border-radius:24px;padding:28px;box-shadow:0 16px 36px #17203316}\n.hero h1{margin:0 0 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print{.nav,.audioBox,.btn{display:none}.card{box-shadow:none;break-inside:avoid}body{background:#fff}.wrapper{padding:0}}\n<\/style>\n<\/head>\n<body>\n<div class=\"wrapper\">\n<section class=\"hero\">\n <h1>CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie<\/h1>\n <p><strong>Premi\u00e8re sp\u00e9cialit\u00e9 physique-chimie<\/strong> – sch\u00e9mas de Lewis, ions, liaisons covalentes, g\u00e9om\u00e9trie et polarit\u00e9.<\/p>\n <div class=\"badges\"><span class=\"badge\">Lewis<\/span><span class=\"badge\">duet \/ octet<\/span><span class=\"badge\">DNL en tirets<\/span><span class=\"badge\">VSEPR simple<\/span><span class=\"badge\">polarit\u00e9<\/span><span class=\"badge\">exercices type bac<\/span><\/div>\n <div class=\"audioBox\"><button onclick=\"readCourse()\">\u25b6 Lecture audio<\/button><button onclick=\"pauseAudio()\">\u23f8 Pause<\/button><button onclick=\"stopAudio()\">\u23f9 Stop<\/button><\/div>\n<\/section>\n\n<nav class=\"nav\">\n <a href=\"#programme\">Programme<\/a><a href=\"#lewis-atome\">Lewis atome<\/a><a href=\"#ions\">Ions<\/a><a href=\"#mol\">Mol\u00e9cules<\/a><a href=\"#geo\">G\u00e9om\u00e9trie<\/a><a href=\"#polarite\">Polarit\u00e9<\/a><a href=\"#exos-html\">Exercices int\u00e9gr\u00e9s<\/a><a href=\"#quiz\">Quiz<\/a>\n <a class=\"btn red\" href=\"https:\/\/pcwallis.malo.wf\/wp-content\/uploads\/2026\/05\/chapitre_structure_entites_geometrie_polarite_premiere_cours.pdf\" target=\"_blank\" rel=\"noopener\">\ud83d\udcc4 PDF cours<\/a>\n <a class=\"btn blue\" href=\"https:\/\/pcwallis.malo.wf\/wp-content\/uploads\/2026\/05\/chapitre_structure_entites_geometrie_polarite_premiere_exercices_types.pdf\" target=\"_blank\" rel=\"noopener\">\ud83e\uddea PDF exercices<\/a>\n<\/nav>\n\n<main id=\"courseText\">\n<section id=\"programme\" class=\"card\">\n<h2>Objectif du chapitre<\/h2>\n<p>Dans ce chapitre, on passe de la composition d’une entit\u00e9 chimique \u00e0 une repr\u00e9sentation exploitable : sch\u00e9ma de Lewis, g\u00e9om\u00e9trie dans l’espace, puis caract\u00e8re polaire ou apolaire.<\/p>\n<div class=\"memo\"><strong>Capacit\u00e9s \u00e0 ma\u00eetriser :<\/strong>\n<ul><li>\u00e9tablir un sch\u00e9ma de Lewis pour une mol\u00e9cule ou un ion simple ;<\/li><li>pr\u00e9voir la g\u00e9om\u00e9trie autour d’un atome central ;<\/li><li>rep\u00e9rer une liaison polaris\u00e9e ;<\/li><li>d\u00e9terminer si une mol\u00e9cule est polaire ou apolaire.<\/li><\/ul><\/div>\n<\/section>\n\n<section id=\"lewis-atome\" class=\"card\">\n<h2>I. Repr\u00e9sentation de Lewis d’un atome<\/h2>\n<p>La repr\u00e9sentation de Lewis montre uniquement les <strong>\u00e9lectrons de valence<\/strong>, c’est-\u00e0-dire les \u00e9lectrons de la couche externe.<\/p>\n<div class=\"warn\"><strong>Convention retenue :<\/strong> un DNL est repr\u00e9sent\u00e9 par un <span class=\"dnl\">tiret<\/span>, pas par deux points. Une liaison covalente est aussi repr\u00e9sent\u00e9e par un trait entre deux atomes.<\/div>\n<h3>M\u00e9thode<\/h3>\n<ol><li>\u00c9crire la configuration \u00e9lectronique.<\/li><li>Compter les \u00e9lectrons de valence.<\/li><li>D\u00e9terminer les \u00e9lectrons c\u00e9libataires utilis\u00e9s pour les liaisons.<\/li><li>Regrouper les \u00e9lectrons restants en <strong>doublets non liants<\/strong> : DNL.<\/li><\/ol>\n<table class=\"table\">\n<tr><th>Atome<\/th><th>Configuration<\/th><th>\u00c9lectrons de valence<\/th><th>Lecture utile<\/th><\/tr>\n<tr><td>H<\/td><td>K<sup>1<\/sup><\/td><td>1<\/td><td>1 liaison pour respecter le duet<\/td><\/tr>\n<tr><td>C<\/td><td>K<sup>2<\/sup> L<sup>4<\/sup><\/td><td>4<\/td><td>4 liaisons<\/td><\/tr>\n<tr><td>N<\/td><td>K<sup>2<\/sup> L<sup>5<\/sup><\/td><td>5<\/td><td>3 liaisons + 1 DNL<\/td><\/tr>\n<tr><td>O<\/td><td>K<sup>2<\/sup> L<sup>6<\/sup><\/td><td>6<\/td><td>2 liaisons + 2 DNL<\/td><\/tr>\n<tr><td>Cl<\/td><td>K<sup>2<\/sup> L<sup>8<\/sup> M<sup>7<\/sup><\/td><td>7<\/td><td>1 liaison + 3 DNL<\/td><\/tr>\n<\/table>\n<div class=\"figure\">\n<svg viewBox=\"0 0 700 210\" aria-label=\"Lewis en tirets\">\n<defs><style>.atom{font:bold 24px system-ui}.dnl{stroke:#b83227;stroke-width:4;stroke-linecap:round}.e{fill:#1d4ed8}.lab{font:13px system-ui;fill:#475569}<\/style><\/defs>\n<text x=\"40\" y=\"35\" class=\"atom\">C<\/text>\n<circle cx=\"52\" cy=\"58\" r=\"4\" class=\"e\"\/><circle cx=\"52\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"28\" cy=\"35\" r=\"4\" class=\"e\"\/><circle cx=\"78\" cy=\"35\" r=\"4\" class=\"e\"\/><text x=\"20\" y=\"92\" class=\"lab\">4 e- c\u00e9libataires<\/text>\n\n<text x=\"190\" y=\"35\" class=\"atom\">N<\/text>\n<circle cx=\"203\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"178\" cy=\"35\" r=\"4\" class=\"e\"\/><circle cx=\"228\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"192\" y1=\"58\" x2=\"214\" y2=\"58\" class=\"dnl\"\/><text x=\"166\" y=\"92\" class=\"lab\">3 liaisons + 1 DNL<\/text>\n\n<text x=\"350\" y=\"35\" class=\"atom\">O<\/text>\n<circle cx=\"363\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"338\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"348\" y1=\"58\" x2=\"370\" y2=\"58\" class=\"dnl\"\/><line x1=\"326\" y1=\"18\" x2=\"326\" y2=\"43\" class=\"dnl\"\/><text x=\"315\" y=\"92\" class=\"lab\">2 liaisons + 2 DNL<\/text>\n\n<text x=\"500\" y=\"35\" class=\"atom\">Cl<\/text>\n<circle cx=\"532\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"502\" y1=\"12\" x2=\"525\" y2=\"12\" class=\"dnl\"\/><line x1=\"502\" y1=\"58\" x2=\"525\" y2=\"58\" class=\"dnl\"\/><line x1=\"486\" y1=\"20\" x2=\"486\" y2=\"48\" class=\"dnl\"\/><text x=\"468\" y=\"92\" class=\"lab\">1 liaison + 3 DNL<\/text>\n\n<text x=\"645\" y=\"35\" class=\"atom\">H<\/text><circle cx=\"656\" cy=\"12\" r=\"4\" class=\"e\"\/><text x=\"624\" y=\"92\" class=\"lab\">1 liaison<\/text>\n<\/svg>\n<div class=\"caption\">Les DNL sont repr\u00e9sent\u00e9s par des tirets rouges.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"ions\" class=\"card\">\n<h2>II. Structure de Lewis d’un ion<\/h2>\n<p>Un ion est une entit\u00e9 charg\u00e9e. Le sch\u00e9ma de Lewis tient compte des \u00e9lectrons gagn\u00e9s ou perdus.<\/p>\n<div class=\"grid\">\n<div class=\"exo\"><strong>Cl<sup>\u2212<\/sup><\/strong> : Cl poss\u00e8de 7 \u00e9lectrons de valence. Il gagne 1 \u00e9lectron, donc il obtient 8 \u00e9lectrons de valence : <span class=\"formula\">4 DNL<\/span>.<\/div>\n<div class=\"exo\"><strong>HO<sup>\u2212<\/sup><\/strong> : l’oxyg\u00e8ne est li\u00e9 \u00e0 H par une liaison O-H et porte des DNL. La charge globale est n\u00e9gative.<\/div>\n<div class=\"exo\"><strong>NH<sub>4<\/sub><sup>+<\/sup><\/strong> : N est li\u00e9 \u00e0 4 H, sans DNL : type AX<sub>4<\/sub>, g\u00e9om\u00e9trie t\u00e9tra\u00e9drique.<\/div>\n<div class=\"exo\"><strong>H<sub>3<\/sub>O<sup>+<\/sup><\/strong> : O est li\u00e9 \u00e0 3 H et poss\u00e8de 1 DNL : type AX<sub>3<\/sub>E, g\u00e9om\u00e9trie pyramidale.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"mol\" class=\"card\">\n<h2>III. Liaison covalente et sch\u00e9ma de Lewis d’une mol\u00e9cule<\/h2>\n<p>Une <strong>liaison covalente<\/strong> est la mise en commun de deux \u00e9lectrons de valence pour former une liaison entre deux atomes.<\/p>\n<p><span class=\"formula\">H respecte le duet ; C, N, O et Cl respectent l’octet.<\/span><\/p>\n<ol><li>Compter les \u00e9lectrons de valence.<\/li><li>D\u00e9terminer combien de liaisons chaque atome doit faire.<\/li><li>Relier les atomes par des traits.<\/li><li>Ajouter les DNL sous forme de tirets.<\/li><li>V\u00e9rifier duet ou octet.<\/li><\/ol>\n<div class=\"figure\">\n<svg viewBox=\"0 0 740 250\">\n<defs><style>.bond{stroke:#172033;stroke-width:4;stroke-linecap:round}.dnl{stroke:#b83227;stroke-width:4;stroke-linecap:round}.a{font:bold 22px system-ui}.t{font:13px system-ui;fill:#475569}.ttl{font:bold 16px system-ui;fill:#1d4ed8}<\/style><\/defs>\n<text x=\"40\" y=\"25\" class=\"ttl\">CH\u2084<\/text><text x=\"82\" y=\"95\" class=\"a\">C<\/text><line x1=\"90\" y1=\"86\" x2=\"90\" y2=\"48\" class=\"bond\"\/><line x1=\"90\" y1=\"105\" x2=\"90\" y2=\"145\" class=\"bond\"\/><line x1=\"78\" y1=\"96\" x2=\"38\" y2=\"96\" class=\"bond\"\/><line x1=\"105\" y1=\"96\" x2=\"145\" y2=\"96\" class=\"bond\"\/><text x=\"85\" y=\"42\">H<\/text><text x=\"85\" y=\"168\">H<\/text><text x=\"18\" y=\"102\">H<\/text><text x=\"152\" y=\"102\">H<\/text><text x=\"45\" y=\"205\" class=\"t\">4 liaisons, 0 DNL<\/text>\n\n<text x=\"235\" y=\"25\" class=\"ttl\">H\u2082O<\/text><text x=\"292\" y=\"95\" class=\"a\">O<\/text><line x1=\"294\" y1=\"105\" x2=\"245\" y2=\"150\" class=\"bond\"\/><line x1=\"310\" y1=\"105\" x2=\"360\" y2=\"150\" class=\"bond\"\/><line x1=\"273\" y1=\"60\" x2=\"303\" y2=\"60\" class=\"dnl\"\/><line x1=\"315\" y1=\"60\" x2=\"345\" y2=\"60\" class=\"dnl\"\/><text x=\"228\" y=\"170\">H<\/text><text x=\"365\" y=\"170\">H<\/text><text x=\"245\" y=\"205\" class=\"t\">2 liaisons, 2 DNL<\/text>\n\n<text x=\"440\" y=\"25\" class=\"ttl\">CO\u2082<\/text><text x=\"438\" y=\"98\" class=\"a\">O<\/text><text x=\"515\" y=\"98\" class=\"a\">C<\/text><text x=\"592\" y=\"98\" class=\"a\">O<\/text><line x1=\"465\" y1=\"88\" x2=\"510\" y2=\"88\" class=\"bond\"\/><line x1=\"465\" y1=\"100\" x2=\"510\" y2=\"100\" class=\"bond\"\/><line x1=\"542\" y1=\"88\" x2=\"587\" y2=\"88\" class=\"bond\"\/><line x1=\"542\" y1=\"100\" x2=\"587\" y2=\"100\" class=\"bond\"\/><line x1=\"430\" y1=\"68\" x2=\"455\" y2=\"68\" class=\"dnl\"\/><line x1=\"430\" y1=\"120\" x2=\"455\" y2=\"120\" class=\"dnl\"\/><line x1=\"592\" y1=\"68\" x2=\"617\" y2=\"68\" class=\"dnl\"\/><line x1=\"592\" y1=\"120\" x2=\"617\" y2=\"120\" class=\"dnl\"\/><text x=\"450\" y=\"205\" class=\"t\">lin\u00e9aire, apolaire<\/text>\n<\/svg>\n<div class=\"caption\">DNL = tirets rouges ; liaisons = traits fonc\u00e9s.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"geo\" class=\"card\">\n<h2>IV. G\u00e9om\u00e9trie d’une entit\u00e9 chimique<\/h2>\n<p>Les doublets \u00e9lectroniques autour d’un atome central se repoussent. Ils se placent pour occuper le maximum de place possible.<\/p>\n<table class=\"table\">\n<tr><th>Type<\/th><th>Autour de l’atome central<\/th><th>G\u00e9om\u00e9trie<\/th><th>Exemples<\/th><\/tr>\n<tr><td>AX<sub>4<\/sub><\/td><td>4 liaisons, 0 DNL<\/td><td>t\u00e9tra\u00e9drique<\/td><td>CH<sub>4<\/sub>, NH<sub>4<\/sub><sup>+<\/sup><\/td><\/tr>\n<tr><td>AX<sub>3<\/sub>E<\/td><td>3 liaisons, 1 DNL<\/td><td>pyramidale \u00e0 base triangulaire<\/td><td>NH<sub>3<\/sub>, H<sub>3<\/sub>O<sup>+<\/sup><\/td><\/tr>\n<tr><td>AX<sub>2<\/sub>E<sub>2<\/sub><\/td><td>2 liaisons, 2 DNL<\/td><td>coud\u00e9e<\/td><td>H<sub>2<\/sub>O, HO<sup>\u2212<\/sup><\/td><\/tr>\n<tr><td>AX<sub>2<\/sub><\/td><td>2 liaisons, 0 DNL<\/td><td>lin\u00e9aire<\/td><td>CO<sub>2<\/sub><\/td><\/tr>\n<\/table>\n<\/section>\n\n<section id=\"polarite\" class=\"card\">\n<h2>V. Polarit\u00e9 d’une liaison et d’une mol\u00e9cule<\/h2>\n<p>L’<strong>\u00e9lectron\u00e9gativit\u00e9<\/strong> est l’aptitude d’un atome \u00e0 attirer vers lui les \u00e9lectrons d’une liaison covalente.<\/p>\n<p>Si deux atomes li\u00e9s ont des \u00e9lectron\u00e9gativit\u00e9s diff\u00e9rentes, la liaison est polaris\u00e9e : l’atome le plus \u00e9lectron\u00e9gatif porte \u03b4\u2212 et l’autre \u03b4+.<\/p>\n<p><span class=\"formula\">Exemple : H<sup>\u03b4+<\/sup> – Cl<sup>\u03b4\u2212<\/sup><\/span><\/p>\n<div class=\"grid\">\n<div class=\"memo\"><strong>H\u2082O est polaire<\/strong> : les liaisons O-H sont polaris\u00e9es vers O et la mol\u00e9cule est coud\u00e9e. Les effets ne se compensent pas.<\/div>\n<div class=\"memo\"><strong>CO\u2082 est apolaire<\/strong> : les liaisons C=O sont polaris\u00e9es, mais la mol\u00e9cule est lin\u00e9aire. Les effets se compensent.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"exos-html\" class=\"card\">\n<h2>VI. Exercices int\u00e9gr\u00e9s au cours<\/h2>\n<div class=\"exo\"><h3>Exercice type 1 – Lewis de N<\/h3><p>Azote : Z = 7. Configuration : K<sup>2<\/sup> L<sup>5<\/sup>. D\u00e9terminer les \u00e9lectrons de valence, le nombre de liaisons et le nombre de DNL.<\/p><\/div>\n<div class=\"corr\"><strong>Correction :<\/strong> N poss\u00e8de 5 \u00e9lectrons de valence. Il lui manque 3 \u00e9lectrons pour l’octet, donc il forme 3 liaisons. Il reste 2 \u00e9lectrons, soit 1 DNL repr\u00e9sent\u00e9 par un tiret.<\/div>\n<div class=\"exo\"><h3>Exercice type 2 – H\u2082O<\/h3><p>Construire Lewis, d\u00e9terminer la g\u00e9om\u00e9trie et conclure sur la polarit\u00e9.<\/p><\/div>\n<div class=\"corr\"><strong>Correction :<\/strong> O forme 2 liaisons O-H et garde 2 DNL. Type AX<sub>2<\/sub>E<sub>2<\/sub>, g\u00e9om\u00e9trie coud\u00e9e. Les liaisons sont polaris\u00e9es vers O et ne se compensent pas : H\u2082O est polaire.<\/div>\n<div class=\"exo\"><h3>Exercice type bac – CO\u2082 \/ NH\u2083 \/ CH\u2084<\/h3><p>Construire Lewis, d\u00e9terminer la g\u00e9om\u00e9trie puis indiquer si la mol\u00e9cule est polaire.<\/p><\/div>\n<div class=\"corr\"><strong>Correction rapide :<\/strong> CO\u2082 : lin\u00e9aire apolaire ; NH\u2083 : pyramidale polaire ; CH\u2084 : t\u00e9tra\u00e9drique apolaire.<\/div>\n<\/section>\n\n<section class=\"card\">\n<h2>Fiche m\u00e9mo<\/h2>\n<table class=\"table\">\n<tr><th>Notion<\/th><th>\u00c0 retenir<\/th><\/tr>\n<tr><td>DNL<\/td><td>doublet non liant repr\u00e9sent\u00e9 par un tiret autour de l’atome<\/td><\/tr>\n<tr><td>Liaison covalente<\/td><td>trait entre deux atomes : mise en commun de deux \u00e9lectrons<\/td><\/tr>\n<tr><td>G\u00e9om\u00e9trie<\/td><td>les liaisons et les DNL se repoussent<\/td><\/tr>\n<tr><td>Polarit\u00e9<\/td><td>liaisons polaris\u00e9es + g\u00e9om\u00e9trie non compens\u00e9e<\/td><\/tr>\n<\/table>\n<\/section>\n\n<section id=\"quiz\" class=\"card quiz\">\n<h2>Quiz de fin de chapitre<\/h2>\n<div data-answer=\"b\"><p><strong>1.<\/strong> Dans ce cours, un DNL est repr\u00e9sent\u00e9 par :<\/p><button>A. deux points<\/button><button>B. un tiret<\/button><button>C. un cercle<\/button><\/div>\n<div data-answer=\"c\"><p><strong>2.<\/strong> Dans H\u2082O, combien l’oxyg\u00e8ne poss\u00e8de-t-il de DNL ?<\/p><button>A. 0<\/button><button>B. 1<\/button><button>C. 2<\/button><\/div>\n<div data-answer=\"a\"><p><strong>3.<\/strong> La g\u00e9om\u00e9trie de NH\u2083 est :<\/p><button>A. pyramidale<\/button><button>B. lin\u00e9aire<\/button><button>C. t\u00e9tra\u00e9drique<\/button><\/div>\n<div data-answer=\"b\"><p><strong>4.<\/strong> CO\u2082 est apolaire parce que :<\/p><button>A. les liaisons ne sont pas polaris\u00e9es<\/button><button>B. les effets se compensent<\/button><button>C. il n’a pas de DNL<\/button><\/div>\n<\/section>\n<\/main>\n<\/div>\n<script>\nlet utterance=null;\nfunction readCourse(){const text=document.getElementById(\"courseText\").innerText;speechSynthesis.cancel();utterance=new SpeechSynthesisUtterance(text);utterance.lang=\"fr-FR\";utterance.rate=0.92;speechSynthesis.speak(utterance);}\nfunction pauseAudio(){if(speechSynthesis.speaking) speechSynthesis.pause();}\nfunction stopAudio(){speechSynthesis.cancel();}\ndocument.querySelectorAll(\".quiz div[data-answer]\").forEach(block=>{const letters=[\"a\",\"b\",\"c\"];block.querySelectorAll(\"button\").forEach((btn,i)=>{btn.onclick=()=>{block.querySelectorAll(\"button\").forEach(b=>b.classList.remove(\"ok\",\"ko\"));btn.classList.add(letters[i]===block.dataset.answer?\"ok\":\"ko\");};});});\n<\/script>\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"<p>CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie Premi\u00e8re sp\u00e9cialit\u00e9 physique-chimie – sch\u00e9mas de Lewis, ions, liaisons covalentes,...<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-877","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/comments?post=877"}],"version-history":[{"count":1,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877\/revisions"}],"predecessor-version":[{"id":879,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877\/revisions\/879"}],"wp:attachment":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/media?parent=877"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":877,"date":"2026-05-29T05:54:37","date_gmt":"2026-05-29T03:54:37","guid":{"rendered":"https:\/\/pcwallis.malo.wf\/?page_id=877"},"modified":"2026-05-29T05:54:38","modified_gmt":"2026-05-29T03:54:38","slug":"structure-lewis-et-geometrie","status":"publish","type":"page","link":"https:\/\/pcwallis.malo.wf\/index.php\/structure-lewis-et-geometrie\/","title":{"rendered":"structure lewis et geom\u00e9trie"},"content":{"rendered":"\n\n\n\n\n\nCH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie<\/title>\n<style>\n:root{\n --bg:#f5f7fb; --ink:#172033; --muted:#5c667a;\n --red:#b83227; --blue:#2457c5; --teal:#087f8c; --green:#2f855a; --violet:#6b46c1; --amber:#b7791f;\n --card:#ffffff; --line:#d6deeb; --soft-blue:#edf4ff; --soft-red:#fff2f0; --soft-green:#effaf5; --soft-violet:#f6f1ff;\n}\n*{box-sizing:border-box}\nbody{margin:0;background:radial-gradient(circle at 10% 0%,#eaf2ff 0,#f7f8fb 32%,#fff 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.ko{background:#fee2e2;border-color:#fca5a5}\n.audioBox{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin-top:12px}\n.audioBox button{border:0;border-radius:12px;padding:10px 13px;background:#111827;color:white;font-weight:700;cursor:pointer}\n.dnl{font-weight:900;color:#b83227;letter-spacing:.08em}\nsvg{max-width:100%;height:auto}\n@media print{.nav,.audioBox,.btn{display:none}.card{box-shadow:none;break-inside:avoid}body{background:#fff}.wrapper{padding:0}}\n<\/style>\n<\/head>\n<body>\n<div class=\"wrapper\">\n<section class=\"hero\">\n <h1>CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie<\/h1>\n <p><strong>Premi\u00e8re sp\u00e9cialit\u00e9 physique-chimie<\/strong> – sch\u00e9mas de Lewis, ions, liaisons covalentes, g\u00e9om\u00e9trie et polarit\u00e9.<\/p>\n <div class=\"badges\"><span class=\"badge\">Lewis<\/span><span class=\"badge\">duet \/ octet<\/span><span class=\"badge\">DNL en tirets<\/span><span class=\"badge\">VSEPR simple<\/span><span class=\"badge\">polarit\u00e9<\/span><span class=\"badge\">exercices type bac<\/span><\/div>\n <div class=\"audioBox\"><button onclick=\"readCourse()\">\u25b6 Lecture audio<\/button><button onclick=\"pauseAudio()\">\u23f8 Pause<\/button><button onclick=\"stopAudio()\">\u23f9 Stop<\/button><\/div>\n<\/section>\n\n<nav class=\"nav\">\n <a href=\"#programme\">Programme<\/a><a href=\"#lewis-atome\">Lewis atome<\/a><a href=\"#ions\">Ions<\/a><a href=\"#mol\">Mol\u00e9cules<\/a><a href=\"#geo\">G\u00e9om\u00e9trie<\/a><a href=\"#polarite\">Polarit\u00e9<\/a><a href=\"#exos-html\">Exercices int\u00e9gr\u00e9s<\/a><a href=\"#quiz\">Quiz<\/a>\n <a class=\"btn red\" href=\"https:\/\/pcwallis.malo.wf\/wp-content\/uploads\/2026\/05\/chapitre_structure_entites_geometrie_polarite_premiere_cours.pdf\" target=\"_blank\" rel=\"noopener\">\ud83d\udcc4 PDF cours<\/a>\n <a class=\"btn blue\" href=\"https:\/\/pcwallis.malo.wf\/wp-content\/uploads\/2026\/05\/chapitre_structure_entites_geometrie_polarite_premiere_exercices_types.pdf\" target=\"_blank\" rel=\"noopener\">\ud83e\uddea PDF exercices<\/a>\n<\/nav>\n\n<main id=\"courseText\">\n<section id=\"programme\" class=\"card\">\n<h2>Objectif du chapitre<\/h2>\n<p>Dans ce chapitre, on passe de la composition d’une entit\u00e9 chimique \u00e0 une repr\u00e9sentation exploitable : sch\u00e9ma de Lewis, g\u00e9om\u00e9trie dans l’espace, puis caract\u00e8re polaire ou apolaire.<\/p>\n<div class=\"memo\"><strong>Capacit\u00e9s \u00e0 ma\u00eetriser :<\/strong>\n<ul><li>\u00e9tablir un sch\u00e9ma de Lewis pour une mol\u00e9cule ou un ion simple ;<\/li><li>pr\u00e9voir la g\u00e9om\u00e9trie autour d’un atome central ;<\/li><li>rep\u00e9rer une liaison polaris\u00e9e ;<\/li><li>d\u00e9terminer si une mol\u00e9cule est polaire ou apolaire.<\/li><\/ul><\/div>\n<\/section>\n\n<section id=\"lewis-atome\" class=\"card\">\n<h2>I. Repr\u00e9sentation de Lewis d’un atome<\/h2>\n<p>La repr\u00e9sentation de Lewis montre uniquement les <strong>\u00e9lectrons de valence<\/strong>, c’est-\u00e0-dire les \u00e9lectrons de la couche externe.<\/p>\n<div class=\"warn\"><strong>Convention retenue :<\/strong> un DNL est repr\u00e9sent\u00e9 par un <span class=\"dnl\">tiret<\/span>, pas par deux points. Une liaison covalente est aussi repr\u00e9sent\u00e9e par un trait entre deux atomes.<\/div>\n<h3>M\u00e9thode<\/h3>\n<ol><li>\u00c9crire la configuration \u00e9lectronique.<\/li><li>Compter les \u00e9lectrons de valence.<\/li><li>D\u00e9terminer les \u00e9lectrons c\u00e9libataires utilis\u00e9s pour les liaisons.<\/li><li>Regrouper les \u00e9lectrons restants en <strong>doublets non liants<\/strong> : DNL.<\/li><\/ol>\n<table class=\"table\">\n<tr><th>Atome<\/th><th>Configuration<\/th><th>\u00c9lectrons de valence<\/th><th>Lecture utile<\/th><\/tr>\n<tr><td>H<\/td><td>K<sup>1<\/sup><\/td><td>1<\/td><td>1 liaison pour respecter le duet<\/td><\/tr>\n<tr><td>C<\/td><td>K<sup>2<\/sup> L<sup>4<\/sup><\/td><td>4<\/td><td>4 liaisons<\/td><\/tr>\n<tr><td>N<\/td><td>K<sup>2<\/sup> L<sup>5<\/sup><\/td><td>5<\/td><td>3 liaisons + 1 DNL<\/td><\/tr>\n<tr><td>O<\/td><td>K<sup>2<\/sup> L<sup>6<\/sup><\/td><td>6<\/td><td>2 liaisons + 2 DNL<\/td><\/tr>\n<tr><td>Cl<\/td><td>K<sup>2<\/sup> L<sup>8<\/sup> M<sup>7<\/sup><\/td><td>7<\/td><td>1 liaison + 3 DNL<\/td><\/tr>\n<\/table>\n<div class=\"figure\">\n<svg viewBox=\"0 0 700 210\" aria-label=\"Lewis en tirets\">\n<defs><style>.atom{font:bold 24px system-ui}.dnl{stroke:#b83227;stroke-width:4;stroke-linecap:round}.e{fill:#1d4ed8}.lab{font:13px system-ui;fill:#475569}<\/style><\/defs>\n<text x=\"40\" y=\"35\" class=\"atom\">C<\/text>\n<circle cx=\"52\" cy=\"58\" r=\"4\" class=\"e\"\/><circle cx=\"52\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"28\" cy=\"35\" r=\"4\" class=\"e\"\/><circle cx=\"78\" cy=\"35\" r=\"4\" class=\"e\"\/><text x=\"20\" y=\"92\" class=\"lab\">4 e- c\u00e9libataires<\/text>\n\n<text x=\"190\" y=\"35\" class=\"atom\">N<\/text>\n<circle cx=\"203\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"178\" cy=\"35\" r=\"4\" class=\"e\"\/><circle cx=\"228\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"192\" y1=\"58\" x2=\"214\" y2=\"58\" class=\"dnl\"\/><text x=\"166\" y=\"92\" class=\"lab\">3 liaisons + 1 DNL<\/text>\n\n<text x=\"350\" y=\"35\" class=\"atom\">O<\/text>\n<circle cx=\"363\" cy=\"12\" r=\"4\" class=\"e\"\/><circle cx=\"338\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"348\" y1=\"58\" x2=\"370\" y2=\"58\" class=\"dnl\"\/><line x1=\"326\" y1=\"18\" x2=\"326\" y2=\"43\" class=\"dnl\"\/><text x=\"315\" y=\"92\" class=\"lab\">2 liaisons + 2 DNL<\/text>\n\n<text x=\"500\" y=\"35\" class=\"atom\">Cl<\/text>\n<circle cx=\"532\" cy=\"35\" r=\"4\" class=\"e\"\/><line x1=\"502\" y1=\"12\" x2=\"525\" y2=\"12\" class=\"dnl\"\/><line x1=\"502\" y1=\"58\" x2=\"525\" y2=\"58\" class=\"dnl\"\/><line x1=\"486\" y1=\"20\" x2=\"486\" y2=\"48\" class=\"dnl\"\/><text x=\"468\" y=\"92\" class=\"lab\">1 liaison + 3 DNL<\/text>\n\n<text x=\"645\" y=\"35\" class=\"atom\">H<\/text><circle cx=\"656\" cy=\"12\" r=\"4\" class=\"e\"\/><text x=\"624\" y=\"92\" class=\"lab\">1 liaison<\/text>\n<\/svg>\n<div class=\"caption\">Les DNL sont repr\u00e9sent\u00e9s par des tirets rouges.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"ions\" class=\"card\">\n<h2>II. Structure de Lewis d’un ion<\/h2>\n<p>Un ion est une entit\u00e9 charg\u00e9e. Le sch\u00e9ma de Lewis tient compte des \u00e9lectrons gagn\u00e9s ou perdus.<\/p>\n<div class=\"grid\">\n<div class=\"exo\"><strong>Cl<sup>\u2212<\/sup><\/strong> : Cl poss\u00e8de 7 \u00e9lectrons de valence. Il gagne 1 \u00e9lectron, donc il obtient 8 \u00e9lectrons de valence : <span class=\"formula\">4 DNL<\/span>.<\/div>\n<div class=\"exo\"><strong>HO<sup>\u2212<\/sup><\/strong> : l’oxyg\u00e8ne est li\u00e9 \u00e0 H par une liaison O-H et porte des DNL. La charge globale est n\u00e9gative.<\/div>\n<div class=\"exo\"><strong>NH<sub>4<\/sub><sup>+<\/sup><\/strong> : N est li\u00e9 \u00e0 4 H, sans DNL : type AX<sub>4<\/sub>, g\u00e9om\u00e9trie t\u00e9tra\u00e9drique.<\/div>\n<div class=\"exo\"><strong>H<sub>3<\/sub>O<sup>+<\/sup><\/strong> : O est li\u00e9 \u00e0 3 H et poss\u00e8de 1 DNL : type AX<sub>3<\/sub>E, g\u00e9om\u00e9trie pyramidale.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"mol\" class=\"card\">\n<h2>III. Liaison covalente et sch\u00e9ma de Lewis d’une mol\u00e9cule<\/h2>\n<p>Une <strong>liaison covalente<\/strong> est la mise en commun de deux \u00e9lectrons de valence pour former une liaison entre deux atomes.<\/p>\n<p><span class=\"formula\">H respecte le duet ; C, N, O et Cl respectent l’octet.<\/span><\/p>\n<ol><li>Compter les \u00e9lectrons de valence.<\/li><li>D\u00e9terminer combien de liaisons chaque atome doit faire.<\/li><li>Relier les atomes par des traits.<\/li><li>Ajouter les DNL sous forme de tirets.<\/li><li>V\u00e9rifier duet ou octet.<\/li><\/ol>\n<div class=\"figure\">\n<svg viewBox=\"0 0 740 250\">\n<defs><style>.bond{stroke:#172033;stroke-width:4;stroke-linecap:round}.dnl{stroke:#b83227;stroke-width:4;stroke-linecap:round}.a{font:bold 22px system-ui}.t{font:13px system-ui;fill:#475569}.ttl{font:bold 16px system-ui;fill:#1d4ed8}<\/style><\/defs>\n<text x=\"40\" y=\"25\" class=\"ttl\">CH\u2084<\/text><text x=\"82\" y=\"95\" class=\"a\">C<\/text><line x1=\"90\" y1=\"86\" x2=\"90\" y2=\"48\" class=\"bond\"\/><line x1=\"90\" y1=\"105\" x2=\"90\" y2=\"145\" class=\"bond\"\/><line x1=\"78\" y1=\"96\" x2=\"38\" y2=\"96\" class=\"bond\"\/><line x1=\"105\" y1=\"96\" x2=\"145\" y2=\"96\" class=\"bond\"\/><text x=\"85\" y=\"42\">H<\/text><text x=\"85\" y=\"168\">H<\/text><text x=\"18\" y=\"102\">H<\/text><text x=\"152\" y=\"102\">H<\/text><text x=\"45\" y=\"205\" class=\"t\">4 liaisons, 0 DNL<\/text>\n\n<text x=\"235\" y=\"25\" class=\"ttl\">H\u2082O<\/text><text x=\"292\" y=\"95\" class=\"a\">O<\/text><line x1=\"294\" y1=\"105\" x2=\"245\" y2=\"150\" class=\"bond\"\/><line x1=\"310\" y1=\"105\" x2=\"360\" y2=\"150\" class=\"bond\"\/><line x1=\"273\" y1=\"60\" x2=\"303\" y2=\"60\" class=\"dnl\"\/><line x1=\"315\" y1=\"60\" x2=\"345\" y2=\"60\" class=\"dnl\"\/><text x=\"228\" y=\"170\">H<\/text><text x=\"365\" y=\"170\">H<\/text><text x=\"245\" y=\"205\" class=\"t\">2 liaisons, 2 DNL<\/text>\n\n<text x=\"440\" y=\"25\" class=\"ttl\">CO\u2082<\/text><text x=\"438\" y=\"98\" class=\"a\">O<\/text><text x=\"515\" y=\"98\" class=\"a\">C<\/text><text x=\"592\" y=\"98\" class=\"a\">O<\/text><line x1=\"465\" y1=\"88\" x2=\"510\" y2=\"88\" class=\"bond\"\/><line x1=\"465\" y1=\"100\" x2=\"510\" y2=\"100\" class=\"bond\"\/><line x1=\"542\" y1=\"88\" x2=\"587\" y2=\"88\" class=\"bond\"\/><line x1=\"542\" y1=\"100\" x2=\"587\" y2=\"100\" class=\"bond\"\/><line x1=\"430\" y1=\"68\" x2=\"455\" y2=\"68\" class=\"dnl\"\/><line x1=\"430\" y1=\"120\" x2=\"455\" y2=\"120\" class=\"dnl\"\/><line x1=\"592\" y1=\"68\" x2=\"617\" y2=\"68\" class=\"dnl\"\/><line x1=\"592\" y1=\"120\" x2=\"617\" y2=\"120\" class=\"dnl\"\/><text x=\"450\" y=\"205\" class=\"t\">lin\u00e9aire, apolaire<\/text>\n<\/svg>\n<div class=\"caption\">DNL = tirets rouges ; liaisons = traits fonc\u00e9s.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"geo\" class=\"card\">\n<h2>IV. G\u00e9om\u00e9trie d’une entit\u00e9 chimique<\/h2>\n<p>Les doublets \u00e9lectroniques autour d’un atome central se repoussent. Ils se placent pour occuper le maximum de place possible.<\/p>\n<table class=\"table\">\n<tr><th>Type<\/th><th>Autour de l’atome central<\/th><th>G\u00e9om\u00e9trie<\/th><th>Exemples<\/th><\/tr>\n<tr><td>AX<sub>4<\/sub><\/td><td>4 liaisons, 0 DNL<\/td><td>t\u00e9tra\u00e9drique<\/td><td>CH<sub>4<\/sub>, NH<sub>4<\/sub><sup>+<\/sup><\/td><\/tr>\n<tr><td>AX<sub>3<\/sub>E<\/td><td>3 liaisons, 1 DNL<\/td><td>pyramidale \u00e0 base triangulaire<\/td><td>NH<sub>3<\/sub>, H<sub>3<\/sub>O<sup>+<\/sup><\/td><\/tr>\n<tr><td>AX<sub>2<\/sub>E<sub>2<\/sub><\/td><td>2 liaisons, 2 DNL<\/td><td>coud\u00e9e<\/td><td>H<sub>2<\/sub>O, HO<sup>\u2212<\/sup><\/td><\/tr>\n<tr><td>AX<sub>2<\/sub><\/td><td>2 liaisons, 0 DNL<\/td><td>lin\u00e9aire<\/td><td>CO<sub>2<\/sub><\/td><\/tr>\n<\/table>\n<\/section>\n\n<section id=\"polarite\" class=\"card\">\n<h2>V. Polarit\u00e9 d’une liaison et d’une mol\u00e9cule<\/h2>\n<p>L’<strong>\u00e9lectron\u00e9gativit\u00e9<\/strong> est l’aptitude d’un atome \u00e0 attirer vers lui les \u00e9lectrons d’une liaison covalente.<\/p>\n<p>Si deux atomes li\u00e9s ont des \u00e9lectron\u00e9gativit\u00e9s diff\u00e9rentes, la liaison est polaris\u00e9e : l’atome le plus \u00e9lectron\u00e9gatif porte \u03b4\u2212 et l’autre \u03b4+.<\/p>\n<p><span class=\"formula\">Exemple : H<sup>\u03b4+<\/sup> – Cl<sup>\u03b4\u2212<\/sup><\/span><\/p>\n<div class=\"grid\">\n<div class=\"memo\"><strong>H\u2082O est polaire<\/strong> : les liaisons O-H sont polaris\u00e9es vers O et la mol\u00e9cule est coud\u00e9e. Les effets ne se compensent pas.<\/div>\n<div class=\"memo\"><strong>CO\u2082 est apolaire<\/strong> : les liaisons C=O sont polaris\u00e9es, mais la mol\u00e9cule est lin\u00e9aire. Les effets se compensent.<\/div>\n<\/div>\n<\/section>\n\n<section id=\"exos-html\" class=\"card\">\n<h2>VI. Exercices int\u00e9gr\u00e9s au cours<\/h2>\n<div class=\"exo\"><h3>Exercice type 1 – Lewis de N<\/h3><p>Azote : Z = 7. Configuration : K<sup>2<\/sup> L<sup>5<\/sup>. D\u00e9terminer les \u00e9lectrons de valence, le nombre de liaisons et le nombre de DNL.<\/p><\/div>\n<div class=\"corr\"><strong>Correction :<\/strong> N poss\u00e8de 5 \u00e9lectrons de valence. Il lui manque 3 \u00e9lectrons pour l’octet, donc il forme 3 liaisons. Il reste 2 \u00e9lectrons, soit 1 DNL repr\u00e9sent\u00e9 par un tiret.<\/div>\n<div class=\"exo\"><h3>Exercice type 2 – H\u2082O<\/h3><p>Construire Lewis, d\u00e9terminer la g\u00e9om\u00e9trie et conclure sur la polarit\u00e9.<\/p><\/div>\n<div class=\"corr\"><strong>Correction :<\/strong> O forme 2 liaisons O-H et garde 2 DNL. Type AX<sub>2<\/sub>E<sub>2<\/sub>, g\u00e9om\u00e9trie coud\u00e9e. Les liaisons sont polaris\u00e9es vers O et ne se compensent pas : H\u2082O est polaire.<\/div>\n<div class=\"exo\"><h3>Exercice type bac – CO\u2082 \/ NH\u2083 \/ CH\u2084<\/h3><p>Construire Lewis, d\u00e9terminer la g\u00e9om\u00e9trie puis indiquer si la mol\u00e9cule est polaire.<\/p><\/div>\n<div class=\"corr\"><strong>Correction rapide :<\/strong> CO\u2082 : lin\u00e9aire apolaire ; NH\u2083 : pyramidale polaire ; CH\u2084 : t\u00e9tra\u00e9drique apolaire.<\/div>\n<\/section>\n\n<section class=\"card\">\n<h2>Fiche m\u00e9mo<\/h2>\n<table class=\"table\">\n<tr><th>Notion<\/th><th>\u00c0 retenir<\/th><\/tr>\n<tr><td>DNL<\/td><td>doublet non liant repr\u00e9sent\u00e9 par un tiret autour de l’atome<\/td><\/tr>\n<tr><td>Liaison covalente<\/td><td>trait entre deux atomes : mise en commun de deux \u00e9lectrons<\/td><\/tr>\n<tr><td>G\u00e9om\u00e9trie<\/td><td>les liaisons et les DNL se repoussent<\/td><\/tr>\n<tr><td>Polarit\u00e9<\/td><td>liaisons polaris\u00e9es + g\u00e9om\u00e9trie non compens\u00e9e<\/td><\/tr>\n<\/table>\n<\/section>\n\n<section id=\"quiz\" class=\"card quiz\">\n<h2>Quiz de fin de chapitre<\/h2>\n<div data-answer=\"b\"><p><strong>1.<\/strong> Dans ce cours, un DNL est repr\u00e9sent\u00e9 par :<\/p><button>A. deux points<\/button><button>B. un tiret<\/button><button>C. un cercle<\/button><\/div>\n<div data-answer=\"c\"><p><strong>2.<\/strong> Dans H\u2082O, combien l’oxyg\u00e8ne poss\u00e8de-t-il de DNL ?<\/p><button>A. 0<\/button><button>B. 1<\/button><button>C. 2<\/button><\/div>\n<div data-answer=\"a\"><p><strong>3.<\/strong> La g\u00e9om\u00e9trie de NH\u2083 est :<\/p><button>A. pyramidale<\/button><button>B. lin\u00e9aire<\/button><button>C. t\u00e9tra\u00e9drique<\/button><\/div>\n<div data-answer=\"b\"><p><strong>4.<\/strong> CO\u2082 est apolaire parce que :<\/p><button>A. les liaisons ne sont pas polaris\u00e9es<\/button><button>B. les effets se compensent<\/button><button>C. il n’a pas de DNL<\/button><\/div>\n<\/section>\n<\/main>\n<\/div>\n<script>\nlet utterance=null;\nfunction readCourse(){const text=document.getElementById(\"courseText\").innerText;speechSynthesis.cancel();utterance=new SpeechSynthesisUtterance(text);utterance.lang=\"fr-FR\";utterance.rate=0.92;speechSynthesis.speak(utterance);}\nfunction pauseAudio(){if(speechSynthesis.speaking) speechSynthesis.pause();}\nfunction stopAudio(){speechSynthesis.cancel();}\ndocument.querySelectorAll(\".quiz div[data-answer]\").forEach(block=>{const letters=[\"a\",\"b\",\"c\"];block.querySelectorAll(\"button\").forEach((btn,i)=>{btn.onclick=()=>{block.querySelectorAll(\"button\").forEach(b=>b.classList.remove(\"ok\",\"ko\"));btn.classList.add(letters[i]===block.dataset.answer?\"ok\":\"ko\");};});});\n<\/script>\n<\/body>\n<\/html>\n","protected":false},"excerpt":{"rendered":"<p>CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie CH10 – Structure d’une entit\u00e9 chimique et g\u00e9om\u00e9trie Premi\u00e8re sp\u00e9cialit\u00e9 physique-chimie – sch\u00e9mas de Lewis, ions, liaisons covalentes,...<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-877","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/comments?post=877"}],"version-history":[{"count":1,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877\/revisions"}],"predecessor-version":[{"id":879,"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/pages\/877\/revisions\/879"}],"wp:attachment":[{"href":"https:\/\/pcwallis.malo.wf\/index.php\/wp-json\/wp\/v2\/media?parent=877"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}