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Notre classe B1.2
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Moyen ge La Peste Noire Le Système Féodal La Route de la Soie Les Croisades L’Urbanisation Les Ville-États Hiérarchie Alliance Une expédition militaire menée par les armées chrétiennes contre les musulmans pour reconquérir la Terre sainte. _____ Système qui domine la plupart des pays d’Europe au Moyen ge avec une structure de classes très rigide. _____ Un pandémie durant le moyen âge qui a tué une grande population d’Europe. _____ Ville au gouvernement autonome, caractérisée par la concentration de richesses et de population. _____ Mouvement de population rurale vers les villes. _____ Un route d’échange entre l’Occident et le Moyen Orient pour les biens de luxe. _____ Point de Bonus: Décrit le terme suivant: Bouc Émissaire:
Make a quiz about the following mini-lab: Mini-Lab: Measuring Reaction Time and Hang Time Objective: In this mini-lab, you will work in groups to measure distances and use calculations to determine your reaction time and hang time. These experiments will help you understand fundamental concepts in physics and reaction time. Materials: Ruler (with metric units) Sticky notes or masking tape A vertical surface (like a wall) Clear space for jumping Calculator (if necessary) Part 1: Measuring Reaction Time Introduction: Reaction time is the time it takes for a person to respond to a stimulus. In this experiment, you will measure distances and use them to calculate your reaction time. Procedure: Preparation: Attach a sticky note or masking tape to the bottom edge of the ruler. Stand facing your partner. Hold the ruler vertically with the zero end at the bottom, lined up with your index finger and thumb. Measurement: Your partner will release the ruler without warning. When you see the ruler fall, try to catch it as quickly as you can. After catching the ruler, measure and record the distance the ruler fell. Data Collection: Each group should repeat the ruler drop experiment three times. Calculate the average distance and record it. Part 2: Calculating Hang Time Introduction: Hang time is the total time a person spends in the air while jumping. In this part of the mini-lab, you will measure distances using tape to mark your jump height and use them to calculate your hang time. Procedure: Preparation: Stand in front of a wall. Reach up as high as you can with your feet flat on the floor. Use a piece of tape to mark this point on the wall. Your partner should stand ready to observe and assist. Measurement: With a loop of tape on your finger, jump as high as you can. Stick the tape on the wall where your fingertips reach when jumping. The difference between the two pieces of tape marks your jumping height. Data Collection: Each group should repeat the jump and measurement three times. Calculations (Make sure to check your units before doing any calculations): Calculating Reaction Time: Use the average distance from Part 1. Calculate the time it took for the ruler to fall using the formula: y = viy t + ½ g t², where viy in this case is zero and "g" is the acceleration due to gravity (approximately 9.81 m/s²). This time is your reaction time. Calculating Hang Time: Use the average jump height difference from Part 2. Calculate the time you spent in the air using the formula: y = viy t + ½ g t². Remember that the velocity at the peak is zero and the total time in the air is twice the time it takes to get to the peak. Conclusion: Discuss your results with your partner and other groups. Compare your reaction times and hang times. Think about factors that may have influenced your results and how you can improve your reaction time and jump height. Consider the real-world applications of understanding reaction time and hang time in physics and sports. Assessment: Work with your partner to write a short report summarizing your findings, including calculations of your reaction time and hang time. Reflect on the factors that may have affected your results and propose improvements to your techniques. Be prepared to discuss your findings in class.
Good day this is Chris today we will be doing a quick walkthrough on ISO 14001 2015 Environmental Management System and its main clauses let's get started ISO 14001 2015 Environmental Management System is a globally recognized standard for environment Management systems or EMS an EMS is a framework that organizations use to manage their environmental impact comply with regulations and improve their environmental performance the standard outlines are requirements for an EMS including the development of an environmental policy the identification of environmental aspects and impacts the establishment of objectives and targets the implementation of operational control monitoring and measurement systems and the ongoing review and Improvement of the system ISO 14001 is a flexible standard that can be used by organizations of any size or type regardless of their environment impact or level of environment performance it provides a practical framework for organizations to manage their environmental impact reduce environment risks and demonstrate their commitment on sustainability to their stakeholders here is the standard that provides a structured approach to develop an EMS which includes several key steps one organizations must develop an environmental policy that outlines their commitment to environmental sustainability this policy should be communicated to all employees and stakeholders two organizations must identify their environmental aspects and impacts this involves identifying the activities products and services that have an impact on the environment as well as the potential environmental consequences of those impacts three once the environmental aspects and the impacts have been identified organizations must establish environmental objectives and targets these objectives and targets should be specific measurable achievable relevant and time-bound 4. after setting objectives and targets organizations must Implement operational controls and establish monitoring and measurement systems to ensure that they are meeting their objectives and targets finally organizations must review and continually improve their EMS this involves conducting regular audits reviewing the EMS to ensure that it remains relevant and effective and making any necessary changes or improvements the main Clause of iso 14001 2015 apart from its scope normative references and terms and conditions that the main Clauses of iso 14001 2015 can be listed as context of the organization leadership planning support operation performance evaluation and Improvement Clause 4.0 context of the organization is about understanding the organization and its context understanding the needs and expectations of the interested parties determining the scope of the Environmental Management System EMS and Environmental Management System itself Clause 5.0 talks about leadership and commitment Environmental Policy organizational roles responsibility and authorities Clause 6.0 planning focuses on actions to address risk and opportunities as well as environmental objectives and planning to achieve them Clause 7.0 support are detailed requirements on resources competence awareness communication that includes external and internal communication documented information that involves creating updating in control of documented information Clause 8.0 operation talks about operational planning and control as well as emergency preparedness and response overall the design of iso 14001 2015 provides guidelines to form a system that is structured to cater the requirements of stakeholder needs and expectations to drive life cycle perspective and Energy Efficiency as pictured here Clause 9.0 performance evaluation provides guidelines to monitoring measurement analysis and evaluation evaluation compliance and management review an additional note here is that ISO 19011 2018 guidelines for auditing Management Systems which is an audit process that will determine the scope to establish the audit criteria by collecting evidence evaluating the evidence and then draw a conclusion based on the findings as pictured here [Music] finally Clause 10.0 Improvement talks about how Improvement is an integral factor to an effective Environmental Management system through General non-conformity and corrective action and continual Improvement talking about Improvement it is always continual in putting efforts towards the betterment of the existing system here is a snapshot of the main Clauses of iso 14001 2015 [Music] I hope you find this video useful we are industry experts specialized in management system consultancy and Industry relevant corporate training give us a call and let us help you drive your business excellence and upskill your employees to elevate workplace efficiency [Music] CREATE 10 MCQ AND 2 SAQ QUESTIONS BASED ON THE ABOVE PARAGRAPH
Changes. Things are always changing, like the clock, the weather, and even me. It seems nothing ever stays the same. My life has been full of changes. Sometimes I don't feel good about them, but then later it gets better. Taffy, my kitty, ran away. We have looked for him all over, but we cannot find him anywhere. I miss Taffy a lot, and I am sad. Dad says that we can get another kitty. That makes me feel better. I don't know what I will name him, but I will always remember Taffy. My best friend, Robin, just moved away. The moving van took away everything, and the house is empty. I wish Robin were here to play with me. Robin now lives in the mountains. I have never seen mountains, but they sound like fun to visit. Mom says we can take an airplane, so I can see Robin and play with her again. The day I started the new school year, I was scared of all the new children in my class. I was afraid that they wouldn't like me, and that I couldn't run as fast as they do. Now I am happy because I have made lots of new friends. I like Sarah and Ana, and Mary Lou, who makes me laugh. I love my class and my teacher. Mom just took a new job at an office downtown. She's not here when I come home from school. My Aunt Barbara is here to give me cookies and milk. Then I wait and wait for Mom to come home. When the hands of the clock point straight up and down, she comes home, and that makes me happy. Things are always changing, even with me. Yesterday I looked in the mirror. My face looked like a Halloween pumpkin because I lost my first tooth. I had a big surprise when I woke up this morning. My tooth was gone from under my pillow. There was a note from the tooth fairy and a whole quarter. I'm going to save it to buy some colored pencils. In school I learned that crawly caterpillars change into butterflies. And tiny acorn nuts grow into great big oak trees. Mom says that long ago, she was little like me. Do you think some day I will change and be a grownup? I think I will be an artist.
EVALUER LE RISQUE CLIENT I Les enjeux liés au risque client II la prise de renseignements pendant la phase commerciale III L’évaluation de la solvabilité d’un prospect ou client 1. A partir du bilan comptable 2. A l’aide d’indicateurs internes IV Les outils d’évaluation des risques I Les enjeux liés au risque client 1. Définition et critères de risques On entend par risque client l’ensemble des situations dans lesquelles le client pourrait compromettre la pérennité du fournisseur. Quelques critères permettent de repérer le risque client : - la taille et l’âge de l’entreprise - le produit qu’elle propose, - son client avec ses propres clients (la sous traitance par exemple induit un lien de dépendance) - le secteur sur lequel elle évolue - la concurrence qu’elle subit - et le montant de ses disponibilités On peut ainsi répartir les degrés de risque : 2. Les impayés clients : première cause de faillite des entreprises Par principe, l’entreprise dépense avant d’encaisser. En accordant des délais de paiement, elle se prive de trésorerie. Elle a alors un besoin en fonds de roulement (BFR), c'est-à -dire besoin de disposer d’une trésorerie d’avance. Tout retard de paiement engendre donc une augmentation du BFR que l’entreprise n’est parfois plus en état de couvrir (découvert bancaire).Lorsque le client est insolvable, c’est un manque de trésorerie qui pèse sur l’entreprise et donc sur sa pérennité. La PME limite donc les risques si certains de ses clients payent comptant. Les entreprises activent donc plusieurs stratégies pour faire face à leurs impayés : 29% gèrent les relances en interne, 24% négocient des facilités de caisse avec leur banque et 19% négocient avec les fournisseurs. II la prise de renseignements pendant la phase commerciale L’entreprise qui souhaite conclure un contrat avec un prospect professionnel peut consulter un certain nombre de documents disponibles auprès d’organismes. Les organismes les plus sollicités sont : - la greffe du tribunal de commerce : elle délivre gratuitement des informations sur les entreprises immatriculées au registre du commerce et des sociétés telles que les statuts, les comptes annuels, l’état d’endettement, l’extrait kbis. L'extrait Kbis représente la véritable « carte d'identité » à jour d'une entreprise immatriculée au Registre du Commerce et des Sociétés (RCS). - les sociétés spécialisées fournissent des informations commerciales et financières, des documents comptables et des analyses payantes permettant de vérifier l’état de santé des entreprises : - les cabinets de recouvrement et sociétés d’assurance : ils réalisent des enquêtes de solvabilité et émettent un avis sur le risque de défaillance sous forme de score ou de note. - Les banques : les entreprises sont notées par les banques. La cotation de la banque mesure la capacité de l’entreprise à honorer ses engagements financiers sur 3 ans. Grâce à cette cotation, la PME peut ainsi , par l’intermédiaire de la banque, vérifier si le prospect ou client est solide financièrement. III L’évaluation de la solvabilité d’un prospect ou client La solvabilité correspond à la capacité de l’entreprise à faire face à ses engagements à long terme. L’entreprise est solvable si la valeur de ses actifs (immobilisations, créances, stocks et disponibilités) est supérieure à ses emprunts et dettes. Une entreprise peut être solvable mais peut manquer de liquidités, c'est-à -dire d’argent disponible au quotidien. La liquidé mesure donc la capacité de l’entreprise à faire face à ses engagements à court terme. 1. A partir du bilan comptable Le bilan comptable fournit des indications sur la santé financière de l’entreprise prospect Les définitions que vous devez maitriser : • Pour l’actif : C’est quoi une Immobilisation ? La notion d'immobilisation intègre l'ensemble des biens durables détenus par une entreprise sur plus d'un exercice comptable et qui ne sont pas destinés à la revente. Les immobilisations financières correspondent aux actifs financiers d'utilisation durable possédés par l'entreprise. Il s'agit notamment des titres de participation, des prêts accordés… Les immobilisations incorporelles comprennent les frais d'établissement, les frais de recherche et développement, les concessions, brevets, licences, marques, logiciels et autres droits similaires, le droit au bail, le fonds commercial. Une immobilisation corporelle correspond à un actif physique que l’entreprise entend utiliser au-delà de la clôture de l’exercice comptable en cours : les terrains, les constructions, l’agencement et les installations générales, l’outillage, le matériel, les véhicules, le mobilier et les équipements informatiques. Que signifie disponibilités ? Le poste "Disponibilités" est constitué des montants détenus en caisse (pièces et billets que l'entreprise possède) et des avoirs en banque (argent détenu sur les comptes bancaires de l'entreprise). On utilise également le terme de trésorerie. C’est quoi une valeur mobilière de placement ? Ce sont des titres financiers, actions ou obligations. En comptabilité, elles correspondent aux excédents de trésorerie placés par l'entreprise. • Pour le passif : Que signifie capitaux propres ? Les capitaux propres sont les ressources financières que possède l'entreprise Le capital social d’une entreprise est égal au montant total des apports de biens et d’argent des associés Que signifie réserves ? Cumul des bénéfices des exercices antérieurs qui n'ont pas été redistribués aux propriétaires de l'entreprise, ni intégrés dans son capital Que signifie résultat ? Il correspond aux ressources restantes à l'entreprise une fois les charges déduites du chiffre d'affaires. 2 A l’aide d’indicateurs internes Une entreprise manque souvent de temps et de moyens pour suivre l’ensemble des ses encours clients. Toutefois, il est nécessaire d’analyser régulièrement certains supports pour anticiper les problèmes de trésorerie. Elle peut - analyser son portefeuille clients via la méthode ABC (vu dans un chapitre précédent), - prendre du recul sur les retards de paiement : le service comptable signale les retards de paiement ou les demandes régulières de report d’échéances. La balance âgée permet de visualiser les clients à relancer Exemple : - mettre en place des indicateurs de suivi des impayés via un tableau Excel Exemple : IV Les outils d’évaluation des risques Les entreprises peuvent se procurer des logiciels dédiés au risque client mais il sont souvent très complexes à utiliser. Certaines entreprises utilisent le crédit management : c’est l’ensemble des procédures financières ou juridiques visant à optimiser le chiffre d’affaires de l’entreprise en accélérant les règlements clients. Une des méthodes de crédit management s’appelle la méthode des points de risque. Elle consiste à classer les clients selon leur risque afin de leur fixer des modalités de paiement adaptés. Elle permet donc d’évaluer les risques de coopération et de se prémunir au cas par cas. Exemple de tableau des points de risque
In our classroom, we believe in teamwork and responsibility. That's why we have different classroom jobs that students can take on to help make our learning environment run smoothly. Each job comes with specific tasks and responsibilities, and it is important for the students to understand the requirements and expectations for each role. Let's take a closer look at the different classroom jobs available to our sixth-grade students: 1. Teacher's Assistant: The Teacher's Assistant plays a crucial role in our classroom. Their main responsibility is to remind the teacher of important tasks that need to be done throughout the day. This includes taking attendance, passing out papers to go home, and any other "do not forget" tasks that the teacher might need help with. The Teacher's Assistant needs to be organized, responsible, and reliable. 2. Supplies Monitor: The Supplies Monitor is responsible for ensuring that all classroom supplies are put away neatly. This includes making sure that pencils, pens, markers, and other materials are returned to their designated places after each use. The Supplies Monitor needs to be attentive to detail and have good organizational skills. 3. Technology Assistant: With our use of technology in the classroom, the Technology Assistant plays a vital role. They help students and guest teachers who might not be tech-savvy with chromebooks and other devices. The Technology Assistant should be comfortable with technology, patient, and willing to help others. 4. Room Monitor: The Room Monitor is in charge of checking desks and floors before lunch dismissal. They make sure that everything is clean and organized before we leave the classroom. The Room Monitor needs to be responsible, observant, and take pride in maintaining a tidy learning environment. 5. Line Leader: The Line Leader has the important task of leading the class and setting the pace when we transition from one place to another. They need to walk in a straight line, follow instructions, and be a positive role model for their peers. The Line Leader should be reliable, responsible, and demonstrate good leadership skills. 6. Messenger: The Messenger is responsible for taking things to the office or picking up items that the teacher needs. They need to be trustworthy, reliable, and able to follow instructions. The Messenger should also have good time management skills to ensure tasks are completed promptly. 7. Host/Hostess: When visitors come to our classroom and need assistance while the teacher is busy, the Host/Hostess is there to help. They greet visitors, provide directions, and offer any necessary support. The Host/Hostess should have good communication skills, be friendly, and approachable. 8. Guest Teacher Guide: In the event of a guest teacher, this student will help them take attendance and assist the teacher with anything they need help with. The Guest Teacher Guide needs to be responsible, reliable, and have good communication skills. They should also be respectful and supportive of the guest teacher. 9. Researcher: During whole-class discussions, if there is a question or topic that needs further exploration, the Researcher steps in. They use the internet to look up information and provide additional insights. The Researcher should have good research skills, be able to navigate online resources, and share accurate information with the class. 10. Secretary: The Secretary takes down notes when directed in the class notebook and collects any papers for absent students, placing them in their designated file. They need to be organized, attentive, and have good handwriting. It is important to note that all of these roles come with certain requirements. To be considered for any of these jobs, you must be punctual and have good attendance. This means arriving to school and class on time every day. Additionally, honesty and reliability are crucial traits for anyone taking on these responsibilities. By working together and taking on these classroom jobs, we can create an environment that is conducive to learning, organized, and supportive. Each of these roles plays a vital part in our classroom community, and we appreciate the efforts of all students who take on these responsibilities. Let's make our classroom a place where everyone feels valued and can thrive!
GRADE 4 Module 6 Lesson 3. Interpret Remainders This PowerPoint file contains instructional aids for teachers who have purchased Into Math. It is intended to be projected to students and used in conjunction with the Student Edition and manipulatives as needed. These slides can be used to move the conversation forward in the classroom, but they should not serve as a replacement for student-centered, collaborative conversations in which students have the space they need to find an entry point, construct meaning, and build understanding.​ ​ About the Slide Presentation​ Presenter View: Use the Presenter view to see notes while presenting. ​ Customization: Add or delete content or notes to get the best learning experience for your classroom. 1 Problem of the Day. Which equations can be used to solve the following problem? Rita makes 40 bracelets and gives an equal number to 8 friends, including Veronica. Veronica gives 2 of the bracelets that she received to her sister. How many bracelets does Veronica have left? A. 40 – 8 = 32 32 ÷ 2 = 16 B. 40 ÷ 8 = 5 5 + 2 = 7 C. 8 + 2 = 10 40 ÷ 10 = 4 D. 40 ÷ 8 = 5 5 – 2 = 3 2 I Can. I Can solve a division problem and interpret the remainder in the context of the problem. 3 Spark Your Learning. Aiden is building solar toy cars in his science club. The cars collect and use energy from the sun for power. Aiden buys 18 wheels. Each car needs 4 wheels. How many cars can Aiden build? Show your thinking. 4 Turn and Talk. What is the remainder in this problem? What does the remainder mean? Professional Development note: Use the Professional Learning Cards to provide language routines that may help students access the meaning of the problem. 5 Build Understanding • Task 1 ACTIVITY. There are 57 students going to the science museum. Each van can take 5 students. How many vans are needed to take all the students? Use a visual model to show how the students are divided into groups of 5. 6 Turn and Talk. How can you use the whole-number quotient and remainder to answer these questions? How many vans will be full? How many students will ride in the van that is not full? Professional Development note: Use the Professional Learning Cards to provide language routines that may help students access the meaning of the problem. 7 Step It Out • Task 2 ACTIVITY.. Amanda has 73 inches of wire for a science experiment. She needs to cut all the wire into 8 identical pieces. How many inches long will each piece be? 8 Turn and Talk. Why is this problem a good situation to write the remainder as a fraction? Professional Development note: Use the Professional Learning Cards to provide language routines that may help students access the meaning of the problem. 9 Check Understanding. 1. Maya needs 44 batteries for smoke alarms. The batteries come in packs of 6. How many packs does Maya need to buy? For 44 ÷ 6, the whole-number quotient is ____ and the remainder is ____. Maya needs to buy ____ packs. Circle how you interpreted the remainder to solve the problem. 10 I Can Scale. 4 I can explain how to solve a division problem and interpret the remainder in the context of the problem. 3 I can solve a division problem and interpret the remainder in the context of the problem. 2 I can solve a division problem and identify the whole-number quotient and the remainder. 1 I can solve a division problem with a remainder. 11 Exit Ticket. Mr. Jenkins’ class is giving speeches during a 46-minute class. Each student will be able to talk for 4 minutes. How many students can give speeches? Justify your answer.
Ions Ions are charged substances that have formed through the gain or loss of electrons. Cations form from the loss of electrons and have a positive charge while anions form through the gain of electrons and have a negative charge. Cation Formation Cations are the positive ions formed by the loss of one or more electrons. The most commonly formed cations of the representative elements are those that involve the loss of all of the valence electrons. Consider the alkali metal sodium (Na) . It has one valence electron in the n=3 energy level. Upon losing that electron, the sodiu ion now has an octet of electrons from the second energy level and a charge of 1+ . The electron arrangement of the sodium ion is now the same as that of the noble gas neon. Consider a similar process with magnesium and aluminum. In this case, the magnesium atom loses its two valence electrons in order to achieve the same arrangement as the noble gas neon and a charge of 2+ . The aluminum atom loses its three valence electrons to have the same electron arrangement as neon and a charge of 3+ . For representative elements under typical conditions, three electrons is usually the maximum number that will be los. Representative elements will not lose electrons beyond their valence because they would have to "break" the octet of the previous energy level which provides stability to the ion. Anions Anions are the negative ions formed from the gain of one or more electrons. When nonmetal atoms gain elections, they often do so until their outermost principal energy level achieves an octet. For fluorine, which has an electron arrangement of (2, 7), it only needs to gain one electron to have the same electron arrangement as neon. Forming an octet (eight electrons in the outer shell) provides stability to the atom. Fluorine will gain one electron and have a charge of 1− . The electron arrangement of the fluoride ion (2, 8) will also change to reflect the gain of an electron. Oxygen has an electron arrangement of (2, 6) and needs to gain two electrons to fill the n=2 energy level and achieve an octet of electrons in the outermost shell. The oxide ion will have a charge of 2− as a result of gaining two electrons. Under typical conditions, three electrons is the maximum that will be gained in the formation of anions. Subatomic Particles in an Ion Since ions form from the gain or loss of electrons, we can also look at the number of subatomic particles (protons, neutrons, and electrons) found in an ion. Remember that the number of protons determines the identity of the element and will not change in a chemical process. Example 2.5.1 How many protons, neutrons, and electrons in a single oxide (O2−) ion? Solution Oxygen has the atomic number 8 so both the atom and the ion will have 8 protons. The average atomic mass of oxygen is 16. Therefore, there will be 8 neutrons (atomic mass−atomic number=neutrons) . A neutral oxygen atom would have 8 electrons. However, the anion has gained two electrons so O2− has 10 electrons. We can also use information about the subatomic particles to determine the identity of an ion. Example 2.5.2 An ion with a 2+ charge has 18 electrons. Determine the identity of the ion. Solution If an ion has a 2+ charge then it must have lost electrons to form the cation. If the ion has 18 electrons and the atom lost 2 to form the ion, then the neutral atom contained 20 electrons. Since it was neutral, it must also have had 20 protons. Therefore the element is calcium. Polyatomic Ions A polyatomic ion is an ion composed of two or more atoms that have a charge as a group (poly = many). The ammonium ion (see figure below) consists of one nitrogen atom and four hydrogen atoms. Together, they comprise a single ion with a 1+ charge and a formula of NH+4 . The hydroxide ion (see figure below) contains one hydrogen atom and one oxygen atom with an overall charge of 1− . The carbonate ion (see figure below) consists of one carbon atom and three oxygen atoms and carries an overall charge of 2− . The formula of the carbonate ion is CO2−3 . The atoms of a polyatomic ion are tightly bonded together and so the entire ion behaves as a single unit. The figures below show several examples. Soult Screenshot 2-2-1.png Figure 2.5.1 : The ammonium ion (NH+4) is a nitrogen atom (blue) bonded to four hydrogen atoms (white). Soult Screenshot 2-2-2.png Figure 2.5.2 : The hydroxide ion (OH−) is an oxygen atom (red) bonded to a hydrogen atom. Soult Screenshot 2-2-3.png Figure 2.5.3 : The carbonate ion (CO2−3) is a carbon atom (black) bonded to three oxygen atoms. The table below lists a number of polyatomic ions by name and by structure. The heading for each column indicates the charge on the polyatomic ions in that group. Note that the vast majority of the ions listed are anions - there are very few polyatomic cations. 1− 2− 3− 1+ Table 2.5.1 : Common Polyatomic Ions acetate, CH3COO− carbonate, CO2−3 arsenate, AsO3−3 ammonium, NH+4 bromate, BrO−3 chromate, CrO2−4 phosphite, PO3−3 chlorate, ClO−3 dichromate, Cr2O2−7 phosphate, PO3−4 chlorite, ClO−2 hydrogen phosphate, HPO2−4 cyanide, CN− oxalate, C2O2−4 dihydrogen phosphate, H2PO−4 peroxide, O2−2 hydrogen carbonate, HCO−3 silicate, SiO2−3 hydrogen sulfate, HSO−4 sulfate, SO2−4 hydrogen sulfide, HS− sulfite, SO2−3 hydroxide, OH− hypochlorite, ClO− nitrate, NO−3 nitrite, NO−2 perchlorate, ClO−4 permanganate, MnO−4 The vast majority of polyatomic ions are anions, many of which end in -ate or -ite. Notice that in some cases such as nitrate (NO−3) and nitrite (NO−2) , there are multiple anions that consist of the same two elements. In these cases, the difference between the ions is the number of oxygen atoms present, while the overall charge is the same. As a class, these are called oxyanions. When there are two oxyanions for a particular element, the one with the greater number of oxygen atoms gets the -ate suffix, while the one with the fewer number of oxygen atoms gets the -ite suffix. The four oxyanions of chlorine are shown below, which also includes the use of the prefixes hypo- and per-. ClO− , hypochlorite ClO−2 , chlorite ClO−3 , chlorate ClO−4 , perchlorate Not your usual ion Soult Screenshot 2-2-4.png "Drink you milk. It's good for your bones." We're told this from early childhood, and with good reason. Milk contains a good supply of calcium, part of the structure of bone. However, there are two other ionic components of hydroxyapatite, the mineral component. Phosphate ion and hydroxide ion make up the remainder of the inorganic material in bone. News You Can Use Bone is a very complex structure. It is composed of protein (mainly collagen), hydroxyapatite (a calcium-phosphate-hydroxide mixture), some other minerals, and contains 10 - 20% water. The calcium/phosphate ratios are not stoichiometric, but vary somewhat from one portion of bone to the next. Bones are very strong but will break under enough stress. Regular exercise and proper nutrition help to increase bone strength. Watch a video about bone structure at http://www.youtube.com/watch?v=d9owEvYdouk Nitrate is an anion with a complex bonding structure. Major sources for this ion in drinking water are runoff from fertilizer, septic tank leakage, sewage, and natural deposits. High concentrations of nitrates represent a significant health hazard, especially to infants. The nitrate in the body is converted to nitrite, which then binds to hemoglobin. This binding decreases the ability of hemoglobin to transport oxygen, thus depriving the cells of the O2 needed for proper functioning. Cyanide production is widespread throughout nature. Forest fires will produce significant amounts of cyanide. Many plants contain cyanide, and it is produced by a number of bacteria, algae, and fungi. Cyanide is used industrially in metal finishing, iron and steel mills, and in organic synthesis processes. This material is also an important component for the refining of precious metals. Formation of a complex between cyanide and gold allows extraction of this metal from a mixture.