{"news":[{"uid":4094,"title":"D\u00e9termination du magn\u00e9sium et du calcium contenu dans des pastilles effervescentes","teasertext":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Voil\u00e0 la troisi\u00e8me et derni\u00e8re partie.","short":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Voil\u00e0 la troisi\u00e8me et derni\u00e8re partie.","body":"
Dur\u00e9e : environ 2 h
Difficult\u00e9 : Elev\u00e9e<\/p>\r\n
Vous trouverez ici<\/a> un t\u00e9l\u00e9chargement PDF de cette fiche d'exercices ainsi que les r\u00e9ponses et les instructions pour pr\u00e9parer l'exp\u00e9rience.<\/p>\r\n Pourquoi ajouter de l\u2019acide HCl 2 M et pourquoi chauffer en partie II.2 et III.2 ?<\/p>\r\n Ecrire l\u2019\u00e9quation de la r\u00e9action du titrage de la partie II ?<\/p>\r\n Calculer la masse totale du cation divalent titr\u00e9 en III, dans la totalit\u00e9 de la pastille. Montrer votre r\u00e9sultat \u00e0 l\u2019assistant.<\/p>\r\n Calculer la masse totale du cation divalent titr\u00e9 en III, dans la totalit\u00e9 de la pastille. Montrer votre r\u00e9sultat \u00e0 l\u2019assistant.<\/p>\r\n Calculer la masse totale du calcium et du magn\u00e9sium pr\u00e9sent dans la pastille.<\/p>\r\n Vous souhaitez d\u00e9j\u00e0 d\u00e9couvrir les trois parties de l'exp\u00e9rience - et plus ? Vous trouverez tout ce qu'il vous faut dans les archives du mat\u00e9riel didactique<\/a> des Olympiades de chimie.<\/p>","datetime":1711403460,"datetimeend":0,"newstype":1,"newstypetext":null,"links":"","subjects":["Exp\u00e9riences"],"image":["https:\/\/chemistry.olympiad.ch\/fileadmin\/_processed_\/5\/c\/csm_IMG_2974_3345478c9f.jpg"],"link":"https:\/\/chemistry.olympiad.ch\/fr\/news\/news\/determination-du-magnesium-et-du-calcium-contenu-dans-des-pastilles-effervescentes","category":[{"uid":3,"title":"Chimie"},{"uid":5,"title":"Startseite"}]},{"uid":4092,"title":"D\u00e9termination de la teneur en magn\u00e9sium dans les pastilles de magn\u00e9sium","teasertext":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Voil\u00e0 la deuxi\u00e8me partie.","short":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Voil\u00e0 la deuxi\u00e8me partie.","body":" Dur\u00e9e: environ 1 h Vous trouverez ici<\/a> un t\u00e9l\u00e9chargement PDF de cette fiche d'exercices ainsi que les r\u00e9ponses et les instructions pour pr\u00e9parer l'exp\u00e9rience.<\/p>\r\n Pourquoi ajouter du HCl 2 M et pourquoi chauffer dans la partie II.2 ?<\/p>\r\n Ecrire l\u2019\u00e9quation de la r\u00e9action de titrage de la partie II.7.<\/p>\r\n Calculer la masse totale de magn\u00e9sium de votre pastille. Montrer votre r\u00e9sultat \u00e0 l\u2019assistant.<\/p>\r\n Vous souhaitez d\u00e9j\u00e0 d\u00e9couvrir les trois parties de l'exp\u00e9rience - et plus ? Vous trouverez tout ce qu'il vous faut dans les archives du mat\u00e9riel didactique<\/a> des Olympiades de chimie.<\/p>","datetime":1708984260,"datetimeend":0,"newstype":1,"newstypetext":null,"links":"","subjects":["Exp\u00e9riences"],"image":["https:\/\/chemistry.olympiad.ch\/fileadmin\/_processed_\/8\/9\/csm_IMG_2971_88e24a1602.jpg"],"link":"https:\/\/chemistry.olympiad.ch\/fr\/news\/news\/determination-de-la-teneur-en-magnesium-dans-les-pastilles-de-magnesium","category":[{"uid":3,"title":"Chimie"},{"uid":5,"title":"Startseite"}]},{"uid":4082,"title":"Des exp\u00e9riences p\u00e9tillantes pour vos cours de chimie","teasertext":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Partie 1: Analyse qualitative de pastilles effervescentes.","short":"Vous \u00eates enseignant.e de chimie \u00e0 la recherche d'id\u00e9es ? Les Olympiades de chimie viennent \u00e0 la rescousse ! Les b\u00e9n\u00e9voles ont divis\u00e9 une exp\u00e9rience de la finale en trois parties adapt\u00e9es \u00e0 l'enseignement, qui seront publi\u00e9es ici. Partie 1: Analyse qualitative de pastilles effervescentes","body":" Dur\u00e9e : environ. 30 minutes Vous trouverez ici<\/a> un t\u00e9l\u00e9chargement PDF de cette fiche d'exercices ainsi que les r\u00e9ponses et les instructions pour pr\u00e9parer l'exp\u00e9rience.<\/p>\r\n <\/p>\r\n Quelle est la composition qualitative en cations divalents de vos pastilles ? Ecrire les \u00e9quations des r\u00e9actions qui ont permis de les identifier.<\/p>\r\n Vous souhaitez d\u00e9j\u00e0 d\u00e9couvrir les trois parties de l'exp\u00e9rience - et plus ? Vous trouverez tout ce qu'il vous faut dans les archives du mat\u00e9riel didactique<\/a> des Olympiades de chimie.<\/p>","datetime":1706551200,"datetimeend":0,"newstype":1,"newstypetext":null,"links":"","subjects":["Exp\u00e9riences"],"image":["https:\/\/chemistry.olympiad.ch\/fileadmin\/_processed_\/d\/0\/csm_IMG_2975_14f56ae0d6.jpg"],"link":"https:\/\/chemistry.olympiad.ch\/fr\/news\/news\/des-experiences-petillantes-pour-vos-cours-de-chimie","category":[{"uid":3,"title":"Chimie"},{"uid":5,"title":"Startseite"}]},{"uid":3944,"title":"A chemical crossword puzzle","teasertext":"October is nobel prize season. The perfect time to revisit the crossword about nobel prizes in chemistry which the Chemistry Olympiad created for this year's OlyDay. Whether you are a chemistry teacher looking for a fun activity for the last lesson of the day or just want to learn more - try it!","short":"October is nobel prize season. The perfect time to revisit the crossword about nobel prizes in chemistry which the Chemistry Olympiad created for this year's OlyDay. Whether you are a chemistry teacher looking for a fun activity for the last lesson of the day or just want to learn more - try it!","body":" DOWNLOAD THE CROSSWORD WITH HINTS AS A PDF<\/a> 114. That is the number of Nobel Prizes awarded in Chemistry between 1901 and 2022. The Nobel Prize is awarded by the Nobel Foundation in Sweden, based on the fortune of Alfred Nobel. He was a scientist and entrepreneur. Nobel achieved the stabilisation and controlled ignition of 1 - Down.<\/strong><\/p>\r\n This was the basis for the introduction of 2 - Down<\/strong> onto the market of explosives, dominated so far by black powder and the key for his fortune made in that industry.<\/p>\r\n The first Nobel Prize in chemistry in 1901 was awarded to Jacobus H. van 't Hoff. A famous equation is named after him, which deals with the temperature-dependence of chemical 3 - Across.<\/strong> Next up, in 1902, Hermann Emil Fischer received the Nobel Prize \u201cin recognition of the extraordinary services he has rendered by his work on sugar and purine syntheses\u201d.<\/p>\r\n If a chemist hears Fischer and sugar in one sentence, one immediately thinks of the Fischer- 4 - Down.<\/strong><\/p>\r\n A certain way of representing a molecule, which is most common in sugar-chemistry. The first Nobel Prize in chemistry to be awarded to a Swiss Chemist was in 1913 to Alfred Werner. Hearing his name, we think of colourful complexes and coordination chemistry. In short, he revolutionised 5 - Across<\/strong> chemistry. What allowed the human population to grow to the extent it is today and supply it with enough food?<\/p>\r\n Many would agree that it is mainly due to the development of the Haber-Bosch process, where nitrogen from the air is turned into 6 - Across<\/strong>. The 6 - Across<\/strong> is then used among other things to synthesise nitrogen-containing fertilisers, which had an enormous impact on agricultural production. For this reason, Fritz Haber was awarded the Nobel Prize in chemistry in 1918.<\/p>\r\n \u201cFor his investigations on 7 - Down<\/strong>, flavins and vitamins A and B2\u201d, in 1937 Paul Karrer, at that time Professor at the university of Z\u00fcrich received the Nobel Prize in chemistry together with Walter Norman Haworth. Karrer was the first person to isolate and structurally identify a vitamin, vitamin A. Later, his structural identification of vitamin B2 enabled the artificial production of the vitamin. Terpenes, a large and diverse class of biomolecules, were investigated and given their name by Leopold Ruzicka, who was a professor at ETH Z\u00fcrich. Together with Adolf Friedrich Johann Butenandt, he received the Nobel Prize in chemistry 1939 for his work on Terpenes and polymethylenes.<\/p>\r\n A wellknown example for a terpene is 8 - Across<\/strong>, which can be found in our blood, cell membranes and its high levels in the blood are associated with atherosclerosis. Robert B. Woodward received the Nobel Prize in chemistry in 1965 \u201cfor his outstanding achievements in the art of organic synthesis\u201d.<\/p>\r\n He is also famous for his total synthesis of 9 - Dow<\/strong>n or cobalamin, which he conducted in collaboration with Albert Eschenmoser from ETH Z\u00fcrich. If you are walking over the ETH Z\u00fcrich campus at H\u00f6nggerberg, you may stumble upon the Vladimir Prelog-Weg. This street is named after one of the recipients of the Nobel Prize in chemistry in 1975 and a former Professor at ETH Z\u00fcrich.<\/p>\r\n Vladimir Prelog, together with John Warcup Cornforth for their work on stereochemistry of organic molecules and reactions and in the case of Cornforth for reactions catalysed by 10 - Down,<\/strong> nature\u2019s catalysts.<\/p>\r\n Today, we wouldn\u2019t want to imagine medicine without the ability to perform an MRI, short for 11 - Down <\/strong>resonance imaging. In 1991, another Swiss Chemist and former Professor at ETH Z\u00fcrich, 2 Richard Ernst, received the Nobel Prize for his contributions into developing high resolution 12 - Down 11 - Down <\/strong>resonance (NMR) spectroscopy.<\/p>\r\n In 2002, Kurt W\u00fcrthrich, Professor for Biophysics at ETH Z\u00fcrich received the Nobel Prize in chemistry together with two other outstanding chemists, John B. Fenn and Koichi Tanaka. W\u00fcrthrich received half of the Nobel Prize in 2002 for his research on 12 - Down 11 - Dow<\/strong>n resonance spectroscopy for the three-dimensional structure determination of biomolecules in solution.<\/p>\r\n Another Swiss Spectroscopist and Biophysicist, Jacques Dubochet was awarded the Nobel Prize in Chemistry in 2017 together with Joachim Frank and Richard Henderson. He is a Professor Emeritus of Biophysics at the University of Lausanne and is famous for playing an important role in the development of cryo- 13 - Down<\/strong> microscopy or short cryo-EM.<\/p>\r\n The most recent Chemistry Nobel Prize in 2022 was awarded to Carolyn Bertozzi, Morten Meldal and Berry Sharpless \u201cfor the development of click chemistry and 14 - Down chemistry\u201d. 14 - Down<\/strong> meaning that the introduced reaction can occur in a biological environment without interfering with any native biochemical reaction.<\/p>\r\n Source: Nobel Prize Foundation. The Nobel Prize, 15 September 2023 https:\/\/www.nobelprize.org\/<\/a><\/p>\r\n <\/p>\r\n SOLUTIONS<\/a><\/p>\r\n <\/p>\r\n This month, the latest Nobel Prize in Chemistry was awarded to Moungi G. Bawendi, Louis E. Brus and Alexei I. Ekimov for the discovery and synthesis of quantum dots.<\/a><\/p>\r\nMat\u00e9riel<\/h2>\r\n
\t
Produits chimiques<\/h2>\r\n
\t
Mode op\u00e9ratoire<\/h2>\r\n
Partie I: Dissolution de la pastille<\/h3>\r\n
\t
Partie II: D\u00e9termination de la teneur totale en cations divalents<\/h3>\r\n
\t
Partie III: D\u00e9termination de la teneur en un seul des deux ions.<\/h3>\r\n
\t
Questions th\u00e9oriques<\/h2>\r\n
Question 1<\/h3>\r\n
Question 2<\/h3>\r\n
Question 3<\/h3>\r\n
Question 4<\/h3>\r\n
Question 5<\/h3>\r\n
Difficult\u00e9: moyenne<\/p>\r\nMat\u00e9riel<\/h2>\r\n
\t
Produits chimiques<\/h2>\r\n
\t
Mode op\u00e9ratoire<\/h2>\r\n
Partie I: Pr\u00e9paration de la solution<\/h3>\r\n
\t
Part II: D\u00e9termination de la teneur en magn\u00e9sium<\/h3>\r\n
\t
Questions th\u00e9oriques<\/h2>\r\n
Question 1<\/h3>\r\n
Question 2<\/h3>\r\n
Question 3<\/h3>\r\n
Difficult\u00e9: Moyenne<\/p>\r\nMat\u00e9riel<\/h2>\r\n
\t
Produits chimiques<\/h2>\r\n
\t
D\u00e9termination de la pr\u00e9sence de cations divalents dans les pastilles \u00e9tudi\u00e9es<\/h2>\r\n
\t
\t
Question th\u00e9orique<\/h2>\r\n
<\/p>\r\n\r\nRelated articles<\/h2>\r\n
\t