Copy of G8 - Reactivity.pdf - GEMS International School

Reactivity Unit https://docs.google.com/document/d/1oRhAI4siJMdKn5_uKgFACspIwcg1BIx1/edit?usp=sharing&ouid=113822886 770520091324&rtpof=true&sd=true Statement of inquiry: Models and patterns describe systems that show relationships between physical and chemical...

Reactivity Unit https://docs.google.com/document/d/1oRhAI4siJMdKn5_uKgFACspIwcg1BIx1/edit?usp=sharing&ouid=113822886 770520091324&rtpof=true&sd=true Statement of inquiry: Models and patterns describe systems that show relationships between physical and chemical properties of elements. Global context: Scientific and technical innovation ATL skills: Self management, thinking, research L1 - Atomic Structure Learning Objectives: Explain that all matter is composed of atoms. Describe the evolution of the atomic model. List the different parts of an atom and give their location and charge. State the relative masses of protons, neutrons and electrons. Compare the sizes of atoms, protons, neutrons and electrons using correct units of measurement and appropriate scientific notation. Describe how electrons are arranged inside atoms.  The basic structure of the periodic table It consists of 8 Columns known as GROUPS Question – Name the metal AND and its symbol 7 rows found at the known as This central block consists of following PERIODS the TRANSITION METALS locations: GROUP 2 PERIOD Potassium K4 Flourine GROUP F 2 7 PERIOD Answers L3 - Group 1 Alkali Metals Where are the alkali metals? Teacher’s Demo: Teacher’s Demo: Watch the demonstration, whilst doing so think about the following questions... 1. How do the group 1 metals react with water? 2. What does the reaction produce? 3. Why are group 1 metals stored under oil? 4. What happens to the reactivity as you go down the group? 5. Why do you think they are also known as alkali metals? Use the labsheet to record your observations on group 1 metals reactivity. Starter: Lithium and water Sodium Pancake Puddle Potassium and water Check point: Lesson objective Self-assessed Progress Start of the End of the lesson lesson State that elements in a column share physical and chemical properties. Describe the physical and chemical properties of the elements in group 1 Properties of Group 1 Metals: Alkali metals: are shiny silver which dull by oxidation. are soft enough to be cut with a knife. have low melting and boiling points. have low density. Lithium, sodium and potassium all float on water. react with water to form alkaline compounds. This is why they are called alkali metals. Properties of Group 1 Metals: Why do you think they are stored under oil? The alkali metals are so reactive that, as elements, they have to be stored in oil. This keeps them from reacting with oxygen in the air. Electron Structure: The alkali metals all have one electron in their outer shell. Why do you think group 1 metals get more reactive as you go down the group? Electron Structure: As you go down Group 1 the atoms become larger and the outer electron is further from the nucleus. The force of attraction between the positively-charged nucleus and the negatively-charged outer electron becomes weaker, which is why the outer electron is more easily lost. Real Life Application Select an element from group 1 alkali metals and describe its applications and uses in real life. Use diagrams to illustrate your ideas. Group 1 metals with water: When group 1 metals react with water they produce; Hydrogen gas and a metal hydroxide. For example; Lithium + Water Lithium hydroxide + Hydrogen 2 Li + 2 H O 2 LiOH + H 2 2 Pick a group 1 element of your choice and write the word and symbol equation for the reaction Group 1 metals with Oxygen: Group 1 metals have to be kept in oil to not react with oxygen and water. When we cut them they are shiny. However, as they begin to react with oxygen in the air they begin to dull, forming a metal oxide. Metal + oxygen Metal oxide Lithium + oxygen lithium oxide 4 Li + O 2 Li O 2 2 We can also react these with oxygen by burning them. They form colourful flames Plenary: Let’s recap from last lesson Success criteria: All students will be able to observe the reaction of the metals. Most students will be able to order the reactivity Some students will be able to explain how the different reactions contribute to the order of the reactivity of group 1 elements Learning Objectives: Describe how electrons are arranged inside atoms. Draw Bohr diagrams. L3 - Electron Configuration Let’s get started  Bohr Diagrams 1) Find your element on the periodic table. 2) Determine the number of electrons – it is the same as the atomic number. 3) This is how many electrons you will draw. Bohr Diagrams Find out which period (row) your element is in. Elements in the 1st period have one shell. Elements in the 2nd period have two shells and so on.  Bohr Diagrams 1) Draw a nucleus with the element symbol inside. C 2) Carbon is in the 2nd period, so it has two energy levels, or shells. 3) Draw the shells around the nucleus.  Bohr Diagrams 1) Add the electrons. 2) Carbon has 6 C electrons. 3) The first shell can only hold 2 electrons.  Bohr Diagrams 1) Add the electrons. 2) Carbon has 6 C electrons. 3) The first shell can only hold 2 electrons.  Bohr Diagrams 1) Since you have 2 electrons already drawn, you need to add 4 more. These go in the 2nd shell. C 2) 3) Add one at a time - starting on the right side and going counter clockwise.  Bohr Diagrams 1) Check your work. 2) You should have 6 total electrons for Carbon. 3) Only two electrons can fit in C 4) the 1st shell. The 2nd shell and upwards can hold up to 8 electrons. You will need your periodic table for this task. Bohr Diagrams Remember number of protons = number of electrons. Try the following elements on your own: a) H C b) c) He O d) Al e) Ne f) K Build an atom simulation: You now have enough knowledge to build your own atoms click the picture below and follow the hyperlink to the simulation. Check point: Let’s check for our understanding Learning Objectives: Lesson objective Self-assessed Progress Start of the End of the lesson lesson State that elements contain Protons, neutrons and Electrons Describe how they are arranged in an atom Use the periodic table to calculate the number of electrons, protons and neutrons. L4 - How Do Metals React With Water? Learning Objectives: Describe how different metals react with water. Compare the reactions of different metals with water. Identify any patterns in your observations and suggest reasons for these patterns.  METALS AND WATER Most metals usually react very slowly with water or not at all. However... There are some exceptions, some metals react quickly with water and some even react violently, bursting into flames and releasing huge amount of energy. METAL + WATER METAL HYDROXIDE + HYDROGEN An example of this type of reaction is: Calcium + water Calcium hydroxide + hydrogen Task: Watch the video below: With the help of footprints science; create a slide to explain what is happening in the video. Imagine that you need to explain it to a group of grade 6 students. Use screen shots from the periodic table animation to help. Consolidate your learning https://www.youtube.com/watch?v= Q4rW0fvkt2g Using the knowledge you have gained so far please complete the following lab. At each stage please take a screenshot of your answers. Starter: Write ideas here….  L5 - Reactivity Series (Displacement Reactions) Learning Objectives: Know the different properties of metals and nonmetals. Explain how the properties of metals are linked to their uses. Use information about the reactions of metals to devise a reactivity series of metals Make predictions about the reactions of metals using the Reactivity Series. Describe the corrosion of metals, and how to prevent it. Understand why different metals have to be extracted from their ores in different ways. Things that make you go hmmm… Order here: These are the magnetic metals: 1) Iron Good conductors of 2) Cobalt Good conductors of heat 3) Nickel electricity Shiny Dense Sonorous High melting point Malleable Ductile  Why do metals tarnish? Metals react with oxygen to form metal oxides in an oxidation reaction. metal + oxygen metal oxide 3 Displacement reaction slide link Read: Metals answer the question in your class books  Potassium Please stop Sodium Calcium calling me a Magnesium Aluminium careless zebra. Carbon Zinc Instead try Iron learning how Tin Lead copper saves Hydrogen Copper gold. Silver Gold Displacement reaction  Starter Match the word to the definition Elements found in the Earth’s crust Metals make up a relatively small proportion of the Earth’s crust and are normally found in rocks as ores Oxygen 46% Silicon 28% Aluminium 8% Iron 5% Calcium 4% Sodium 3% Magnesium 2% Potassium 2% Titanium 0.5% Hydrogen 0.5% All other 1% The Reactivity Series Very reactive Potassium (K) extracted by electrolysis Sodium (Na) Calcium (Ca) Magnesium (Mg) Aluminium (Al) -----------------------Carbon (C)----------------------- Fairly reactive Zinc (Zn) reduced with Carbon Iron (Fe) Lead (Pb) Copper (Cu) ---------------------Hydrogen (H)--------------------- Not at all reactive Silver (Ag) don’t need extracting Native metals Gold (Au) Platinum (Pt) How do we extract metals A displacement reaction is one where a MORE REACTIVE metal will DISPLACE a LESS REACTIVE metal from a compound. + + Angelina is more reactive than Jennifer… …. So Angelina displaces Jennifer and wins Brad! This could be used to extract metals from ores, but we Don’t want to use up one metal to extract another – Found as a metal ore: A naturally occurring compound found in the Earth’s crust. Needs to be chemically separated before the metal can be used as an element. Found as a native metal: occurs in pure form in the Earth’s crust Many metal ores are oxides. To obtain the metal, the oxygen must be removed by reduction. METALS ORES Rocks that contain metals are called ores. Hematite (iron ore) Bauxite (Aluminium ore) Recycling metals: There are four stages to extracting metal from an ore: Saves money. Reserves of metal last longer. 1. The ore is mined 2. The ore is separated from its impurities avoids waste and pollution. 3. The ore is converted to a metal reduces environmental 4. The metal formed is then purified effects of mining. Saves energy. watch  EXTRACTING METALS Reactive metals that have combined with other elements in rocks have to be extracted. There are two ways that we can extract metals. The first is using a displacement reaction. A displacement reaction occurs when a more reactive metals pushes (displaces) a less reactive metal out of a solution. Cu O Cu C O Cu O C Cu O  Potassium Please stop Sodium Calcium calling me a Magnesium Aluminium careless zebra. Carbon Zinc Instead try Iron learning how Tin Lead copper saves Hydrogen Copper gold. Silver Gold Extension Tasks: Complete the following assessments Assessment 1 Physical Properties of Metals and Nonmetals http://www.ck12.org/assessment/ui/views/test.view.new.html?practice/Metals-Practice?type=practice&referrer=f eatured_content&ep=http://www.ck12.org/chemistry/Metals/? Assessment 2 Reactivity Series of Metals http://www.ck12.org/chemistry/Direct-Redox-Reactions/?by=ck12&difficulty=all#assessment  Now answer the questions… 1. Zinc oxide + calcium 🡪 REACTION 2. Magnesium + iron oxide 🡪 REACTION 3. Zinc + tin oxide 🡪 REACTION 4. Magnesium sulphate + Zinc 🡪 NO REACTION 5. Calcium + copper oxide 🡪 REACTION 6. Magnesium + iron sulphate 🡪 REACTION 7. Tin oxide + Copper 🡪 NO REACTION 8. Gold + copper oxide 🡪 NO REACTION  Now answer the questions… 1. Zinc oxide + calcium 🡪 Calcium oxide + Zinc 2. Magnesium + iron oxide 🡪 Magnesium oxide + Iron 3. Zinc + tin oxide 🡪 Zinc oxide + Tin 4. Magnesium sulphate + Zinc 🡪 NO REACTION 5. Calcium + copper oxide 🡪 Calcium oxide + Copper 6. Magnesium + iron sulphate 🡪 Magnesium sulphate + Iron 7. Tin oxide + Copper 🡪 NO REACTION 8. Gold + copper oxide 🡪 NO REACTION  Displacement Worksheet 1. Copper Sulphate + Magnesium 🡪 ___________+__________ Sulphate 2. Copper Sulphate + Zinc 🡪 ___________+__________ Sulphate 3. Zinc Sulphate + Magnesium 🡪 ___________+__________ _________ 4. Zinc Sulphate + Copper 🡪 ___________+__________ Sulphate 5. Tin Chloride + Zinc 🡪 ___________+__________ __________ 6. Magnesium Nitrate + Copper 🡪 ___________+__________ __________  Learning Activity Complete the Displacement Worksheet. 1. Copper Sulphate + Magnesium 🡪 ___________+__________ Copper Magnesium Sulphate 2. Copper Sulphate + Zinc 🡪 Copper Zinc ___________+__________ Sulphate Zinc Magnesium 3. Zinc Sulphate + Magnesium 🡪 ___________+__________ Sulphate 4. Zinc Sulphate + Copper 🡪 Copper Zinc ___________+__________ Sulphate 5. Tin Chloride + Zinc 🡪 Tin Zinc ___________+__________ __________ Chloride Magnesium Nitrate 6. Magnesium Nitrate + Copper 🡪 ___________+__________ Copper __________ Extension: Grade A Balancing symbol equations 5 minutes L6 - Ions and Ionic Bonding Learning Objectives: Describe an ion and recognize one from its formula Model how ionic bonding takes place.  What are ions? Electrons have a negative charge Atoms have NO OVERALL CHARGE. What happens if an atom loses or picks up one or more electrons? Where would these electrons come from in the atom? (think about your independent study task) Let’s see an example… Click on me!! Remember that the proton number tells you how many protons or electrons the atom has. Not any more!!! Why not?? An ion is shown like this to show the electron shells Or simply like this That’s how positive ions are formed. So how do you think negative ions are formed? Use your ‘show-me’ board to sketch out an atom of fluorine, and show how it could form a negative ion. Ions Summary: Group 1 elements form 1+ ions Group 2 elements form 2+ ions Group 3 elements form 3+ ions Group 5 elements form 3- ions Group 6 elements form 2- ions Group 7 elements form 1- ions  Modelling Ionic Bonding Your task is to use the whiteboards, desks, or even yourselves (?!) to create ions from two different elements. You must show how the electrons that are transferred from one to the other Use your ‘Cordy’s Golden Rules for Ionic Bonding’ sheet to work out how the atoms can bond together by transferring electrons  Progress Check Use the small whiteboards to scribble down answers to these as fast as you can! ✔ What is the charge of an electron? ✔ What is the charge of an atom? ✔ What is the charge of an ion when it has gained an electron? ✔ How many electrons can one atom of sodium give to an atom of chlorine? (Think about what group sodium is in) ✔ Why are two sodium atoms needed to make sodium oxide? L7 - Ionic Compounds  RECAP - Ions form when elements try to get full outer shells - Ions will gain or lose electrons, depending on what takes the least amount of energy - If an ion gains negative electrons, it becomes negative - If an ion loses negative electrons, it becomes positive  RECAP If an ion loses negative electrons, it becomes positive If it loses 1 electron, it gets a + charge Mg2+ If it loses 2 electron, it gets a +2 charge If it loses 3 electrons, it gets a +3 charge If an ion gains negative electrons, it becomes negative If it gains 1 electron, it gets a - charge If it gains 2 electrons, it gets a 2- F- charge If it gains 3 electrons, it gets a 3- charge  Starter Stick the image down in your book. Around the outside, add these labels in the correct places: - Has a positive charge because it lost electrons - Has a full outer shell - Has an electron configuration of 2, 8, 1 - Needs to gain 1 electron - Needs to lose 1 electron - Has an electron configuration of 2, 8 - Has a negative charge because it gained electron  Ionic Compound A positive cation and a negative anion can combine in a chemical reaction to form an ionic compound. Ionic compounds are held together by strong bonds. This is because they have opposite charges Positive and negative attract  Ionic Compound Cations lose electrons Transfer of electrons Anions gain electrons Cations are electrostatically attracted to the oppositely charged anions when forming an ionic compound.  Ionic Compound The magnesium ion loses two electrons The chloride ion gains 1 electron only One magnesium ion will transfer its electrons to two chloride ions to make an ionic compound  Ionic Compound The Sodium loses 1 electron The oxygen ion needs to gain 2 electrons Two Sodium ions ill transfer their electrons to one one oxygen ion to make an ionic compound  Writing Ionic Formula How do we write the formula for ionic compounds? - Write the cation and its charge first - Write and anion and its charge - Draw an arrow - Show the product Li+ + O2- Li2O  The shortcut 1. If the two ions have the same charge, then the charges are dropped. Ca2+ + O2- → Ca0 Na+ + Cl- → NaCl 2. If the charges are different, you swap and drop them below Remember- we don’t write Na+ + S2- → Na2S a number when there is Fe3+ + Cl- → FeCl3 only one atom  Swap & Drop If the charges are different, swap and drop Al3+ + O2- → Al2O3 This means that there needs to be two alimunium ions for every 3 oxides Fe3+ + S2- → Fe2S3 This means there needs to be 2 iron ions for every 3 sulfides  Complete these into your books 1. Na+ + Cl- 4. Na+ + O2- 2. Al3+ + S2- 5. Mg2+ + O2- 3. Cu2+ + O2- 6. Fe3+ + O2-  1.NaCl 2.Al2S3 Answers 3.CuO 4.Na2O 5.MgCl2 6.Fe2O3 89  Musical Compounds Take an ion card, and an answer sheet You will move around the room while the music is playing, hiding your ion card When the music stops, pair up with the closest person If you have a cation (positive) and an anion (negative) write the ionic compound it would form If you have two cations or two anions, don’t write anything Keep going until you have a full table of ionic compounds, then go back to your seat. Then stick it down into your book Naming Ionic Compounds The cation is always named first then the anion. The cation is named as the element name (without any change). The anion is named as the first part of the element name, with changing the suffix into -ide. Now go back to the previous exercise and name the ionic compounds that you formed. L8 - Covalent Bonding Starter: Describe the concept on which covalent bond is formed. Think-Pair and Share: How do you think covalent bonds are formed? Bonds in all the polyatomics and diatomics are all covalent bonds O3 -O2- Cl2-H2 What is a covalent bond? Compounds can contain more than one covalent bond. Oxygen (2.6) needs two more electrons, but hydrogen (1) only needs one more. How can these elements be joined by covalent bonding? The oxygen atom shares one electron with one hydrogen atom, and a second electron O with another hydrogen atom. H H What is the name of the molecule that is formed? H2O (or H–O–H) is water. Covalent bond for water molecule Learning Objective: Deduce the names for simple binary ionic compounds. Rules for ionic compounds