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Making fuel from vegetable oil Site éducatif : The Naked Scientists ... UK, have a found a simple way to use vegetable oil as fuel for car engines for example.
Fiche de présentation de la ressource

|Classe : 1ère STL |Enseignement : LV et enseignements | | |technologiques |

|THEMES du programme : |SOUS-THEMES du programme : | |SPC : Chimie et développement |SPC : chimie : enjeux sociétaux, | |durable |économiques et environnementaux | |CBSV : Thème 1 : Les systèmes |CBSV : 1.5. Les molécules des organismes| |vivants présentent une |vivants présentent des structures et des| |organisation particulière de la|propriétés spécifiques | |matière. | |

|Titre : Biofuels |

Extrait du BOEN

|Connaissances SPC |capacités SPC | |1) Champs d’application de la chimie |1) Citer : – l’intervention de la| |et évolution des techniques. |chimie dans divers domaines de la| |Aspects historiques et économiques. |vie courante ; – l’évolution | | |d’une technique au cours des | | |siècles ; des choix opérés pour | | |répondre à des besoins sociétaux | | |et/ou économiques. Prendre | | |conscience du lien entre science | |2) La chimie face à l’environnement. |et technique. | |Rôle de la chimie dans des | | |problématiques liées à |2) Citer des implications de la | |l’environnement. |chimie dans des études menées sur| |Impact environnementaux des synthèses |l’environnement ou des actions | |et des |visant à le préserver. | |analyses. |Choisir parmi plusieurs procédés,| | |celui qui minimise les impacts | |3) Synthèses organiques. |environnementaux. | |Acides et dérivés (estérification, | | |hydrolyse) |3) Reconnaître les réactions | | |d’aldolisation, de crotonisation,| | |d’estérification et d’hydrolyse. | |Connaissances CBSV |capacités CBSV | |1) Les organismes vivants sont |1) Exploiter des ressources | |essentiellement constitués d’atomes de|documentaires | |C, H, O, N, P et S | | | |2) Représenter la structure | |2) Ces atomes sont reliés entre eux |générique d’un aldohexose, d’un | |par des liaisons covalentes pour |acide aminé et d’un acide gras. | |constituer des biomolécules: lipides, | | |protéines, acides nucléiques et | | |polyosides. | | |Les acides gras comportent une longue | | |chaîne carbonée et une fonction acide | | |carboxylique. | |

Compétences transversales et attitudes

▪ Mobiliser ses connaissances ▪ Rechercher, extraire, organiser des informations utiles ▪ Raisonner, argumenter, démontrer ▪ Travailler en équipe

Type de ressource

▪ Activité documentaire ▪ Réinvestissement et approfondissement ▪ Résumé du contenu de la ressource (et conditions de mise en oeuvre si besoin) :

Il s’agit d’une séquence transversale car elle allie l’enseignement de SPC à la CBSV et à l’enseignement scientifique en langues vivantes. Il s’agit de découvrir à travers trois ressources documentaires (un MP3, deux vidéos) l’utilisation d’algues comme source d’énergie alternative. Une activité récapitulative est prévue en fin de séquence : un jeu de TABOO qui permet de revoir tout le nouveau vocabulaire abordé. Cette séquence permet le travail en binômes, par groupes de 4-5 et en classe entière. Elle favorise l’utilisation de l’oral dans l’apprentissage des langues. Elle contient d’autre part les réponses en APPENDIX.

Niveau requis et fichiers sources

|Langue cible |Anglais | |Niveau requis |Compréhension écrite : B1 Compréhension orale :| | |B1 | | |Expression orale : B1 Prendre part à | | |une conversation : B1 | | |Niveaux définis dans le Cadre Commun de référence | | |pour les Langues : | | |http://fr.wikipedia.org/wiki/Cadre_européen_commun_d| | |e_référence_pour_les_langues | |Nombre de séances |3 séances : | | |1) Etude du MP3 (en salle multimédia ou salle | | |équipée d’enceintes audios) | | |2) Etude des deux vidéos (1h en salle multimédia) | | |3) Jeu de taboo en salle de cours classique |

|Documents choisis | |Document 1 |Making fuel from vegetable oil Site | | |éducatif : The Naked Scientists | | |http://www.thenakedscientists.com/HTML/content/interview| | |s/interview/760/ | |Document 2 |Ecopolis biofuels | | |Site éducatif : howstuff works | | |http://videos.howstuffworks.com/science-channel/34234-ec| | |opolis-biofuel-video.htm | |Document 3 |Invention nation : algae biofuel | | |Site éducatif : howstuff works | | |http://videos.howstuffworks.com/science-channel/37592-in| | |vention-nation-algae-biofuel-video.htm |

|Mots clés de recherche : bioénergie, biocarburant, anglais, algues, | |CBSV, environnement |

|Provenance : CANU Cécile, [email protected] | BIOFUELS

1. kitchen science : Making fuel from vegetable oil

Scientists at Bath University, UK, have a found a simple way to use vegetable oil as fuel for car engines for example.

Here is an interview at Bath University by Azi, reporter from the Naked Scientists.

STEP 1: Discover the recording

http://www.thenakedscientists.com/HTML/content/interviews/interview/760/ Listen to the MP3 without looking at the transcript at least two or three times. STOP at “glycerol, which is just a waste product of the biodiesel process »

Write down the keywords that you hear, then write them on the board:

____________________________________________________________________________ ____

____________________________________________________________________________ ____

STEP 2: Rephrasing

Get into groups of 4-5 students.

Using the keywords selected by the class, rephrase the main ideas in the MP3 :

____________________________________________________________________________ ____

____________________________________________________________________________ ____

After having written your summary, one student from each group should read it or explain it to the rest of the class.

STEP 3: Assisted listening

After a couple of listenings without the text, you may listen to the MP3 again but this time, read the text at the same time.

Note that the main keywords appear in bold lettering.

Transcript: http://www.thenakedscientists.com/HTML/content/interviews/interview/760/

Kitchen Science - Making Fuel from Vegetable Oil

Prof. Matthew Davidson, Prof. Gary Hallway & Chris Chuck, University of Bath

Azi - Hello, welcome to Kitchen Science. This week, I’ve come to the historic city of Bath and I’m actually standing at the university of Bath’s Chemistry Department, I’m joined by Professor [Matthew] Davidson and also Christopher Chuck who is a PhD student here. The question I’ve come to you guys with, and I’m really hoping you can help me out here, is can you run your car on cooking vegetable oil?

Matthew - That’s an interesting question as to whether you can run your car on vegetable oil, what’s chemically called a triglyceride, a molecule with three long fatty arms on it. What happens is they all just get entangled together, and that means it has a very high melting point. The two most important problems are; firstly the stuff would freeze in your tank, so on a slightly cold morning you would have a solid mess and the second problem is that it simply doesn’t burn very well. Azi - Okay, so what’s the solution?

Matthew - Well the solution is actually quite a simple chemical process, and I can show you exactly how we do it. Before we do, I want you to put on some goggles, just to make sure we’re safe.

Azi - Okay, I’ve got my goggles on.

Matthew - Right, well what we’re going to do is were just going to take some vegetable oil that we bought at the supermarket, and we’re going to take this mixture here, which is methanol and sodium hydroxide. We’re just going to mix it with vegetable oil, you can see that the vegetable oil is stirring away with a stirrer in it, it’s heated up to about 60 or 70 degrees centigrade.

Azi - Okay, so you’ve got the vegetable oil in a flask, and you’re putting sodium hydroxide which is mixed with methanol, in the measuring cylinder and you’re going to tip it in…

Matthew - Yeah, we need to wait about half an hour and what we will see is the separate components; the biodiesel will separate out from the by- product which is called glycerol, which is the other part of the fatty molecule that we started off with.

Azi - So what’s the chemical process that is happening inside that flask? [pic] Matthew - Well the chemical process is something called transesterification, which is a bit of a complicated term for simply just changing the end of the long fatty molecule (molecule 1). So instead of just having 3 of the fatty molecules attached to one end, a bit like a piano stool with three legs, we’re changing the end, just capping off the fatty molecule with methanol (molecule 2). That give us individual fatty molecules, and that’s what is actually called biodiesel (molecule 3), that we could use in an engine; and another molecule called glycerol (molecule 4), which is just a waste product of the biodiesel process. STOP!

STEP 4: Pair work on vocabulary

Get into pairs. Here some definitions, try to match them with the correct words found in the text above:

|French or formula |English | |moteur | | |produit secondaire | | |Résidu, déchet | | |Corps gras | | |Éprouvette graduée | | |Agiter, mélanger | | |Lunettes de protection | | |geler | | |Réservoir de voiture | | |emmêlé | | |[pic] | | |[pic] | |

2. REACTION

Fill in the blanks, on the left handside, the reactants, and catalyst, on the right handside, the products and catalyst.



[pic] = [pic]



3. biofuels from algae

Discover now how biofuel could be produced from algae:

http://videos.howstuffworks.com/science-channel/34234-ecopolis-biofuel- video.htm

Answer the following questions: In which state does biologist Glen Curts work? ____________________________________________________________________________ ______ What can be used (in this video) to produce biofuels? ____________________________________________________________________________ ______ Why do some environmentalists say that biofuels are an ecological disaster? ____________________________________________________________________________ ______ ____________________________________________________________________________ ______ If the US had to grow plants in order to produce enough biofuels for their energy needs, which percentage of the surface area of the country would they use? ____________________________________________________________________________ ______ Which chemicals of interest do algae contain? ____________________________________________________________________________ ______

4. INVENTION NATION : ALGAE BIOFUEL

For further knowledge on algae biofuels, watch:

http://videos.howstuffworks.com/science-channel/37592-invention-nation- algae-biofuel-video.htm

Cross out the wrong answer: TRUE OR FALSE The three students are experts in algae biofuel: TRUE - FALSE Dr. Patrick Hatcher teaches biology: TRUE - FALSE The lab is developing an algae strain* with a maximum content of oil: TRUE - FALSE * a strain = a race, a species The scientists want to heat the algae at 450°C in order to extract the oil: TRUE - FALSE

5. PLAYING TABOO to review the essentials

On the next page, you will find taboo cards that will help you review the important vocabulary.

Objective: you have to make your team guess the word on the card you randomly pick without using the word itself or three additional words listed on the card. A team that guesses a word gets one point.

How to play:

- Get into two teams, decide on the teams’ names.

- Cut out the cards and place one set on the teacher’s desk.

- A student who gets a right answer gets to come to the front and make the others guess a word. He must first randomly pick a card from the pile.

- Students take turns to come to the front to make the others guess one word.

- The game stops after all 12 cards have been used.

[pic] [pic]

APPENDIX: Answers

1. kitchen science : Making fuel from vegetable oil

STEP 4: Pair work on vocabulary

|French or formula |English | |moteur |engine | |produit secondaire |By product | |Résidu, déchet |Waste product | |Corps gras |Fatty molecule | |Éprouvette graduée |Measuring cylinder | |Agiter, mélanger |To stir (or to mix) | |Lunettes de protection |goggles | |geler |To freeze | |Réservoir de voiture |tank | |emmêlé |entangled | |[pic] |glycerol | |[pic] |triglyceride |

6. REACTION



[pic] = [pic]

7. biofuels from algae

Discover now how biofuel could be produced from algae:

http://videos.howstuffworks.com/science-channel/34234-ecopolis-biofuel- video.htm

Answer the following questions: In which state does biologist Curts work? He works in Texas What can be used (in this video) to produce biofuels? They first refer to plants Why do some environmentalists say that biofuels are an ecological disaster? Biofuels could use soil that could not then be used to grow plants to feed the planet. If the US had to grow plants in order to produce enough biofuels for their energy needs, which percentage of the surface area of the country would they use? Over 100% would need to be used to that purpose! Which chemicals of interest do algae contain? Some strains of algae contain large quantities of lipids, ie fatty molecules.

8. INVENTION NATION : ALGAE BIOFUEL

For further knowledge on algae biofuels, watch:

http://videos.howstuffworks.com/science-channel/37592-invention-nation- algae-biofuel-video.htm

Cross out the wrong answer: TRUE OR FALSE The three students are experts in algae biofuel: TRUE - FALSE Dr. Patrick Hatcher teaches biology: TRUE - FALSE The lab is developing an algae strain* with a maximum content of oil: TRUE - FALSE * a strain = a race, a species The scientists want to heat the algae at 450°C in order to extract the oil: TRUE - FALSE

-----------------------

[pic] Source : http://commons.wikimedia.org/wiki/File:Biofuels.jpg

Prof. Matthew Davidson, University of Bath Source: http://www.thenakedscientists.com/HTML/content/interviews/interview/760/

[pic]

Biofuel : 1) 2) 3)





Temperature =

glycerol

Biofuel : 3 esters

triglyceride

Hydroxide ions

Hydroxide ions

methanol

Temperature = 60 to 70°C

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