Chemical patterns Route map Over the next 12 lessons you will study : Friday 21 October 2011 C4.1 The periodic table C4.2 The alkaline metals C4.3 Chemical equations C4.4 The halogens End of module test C4.5 The discovery of helium C4.6 Atomic structure C4.7 Electrons in atoms C4.8 Electronic structures and periodic table C4.9 Salts C4.10 Ionic theory C4.11 Ionic theory and atomic structure C4.12 Chemical species
C4.7 Electrons in atoms Decide whether the following statements are true or false:
Know that electrons are arranged in shells around a positive nucleus
Know that each elements has its own unique electronic configuration
Know that elements in different shells have different energy levels
Friday 21 October 2011 First activity: Electrons are important in both chemistry and of course physics. Electrons that flow around a conducting material like a metal wire do what in circuits ? PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers Literacy: Atom, proton, electron, neutron, electron configuration, elements, electron shells, nucleus, charges and atomic structure. Numeracy: In 1 gram of hydrogen or 12 grams of carbon or 16 grams of oxygen there are exactly 6.02 x 10 23 atoms. It is this number of atoms that give each element its own relative atomic mass We will focus on exploring issues or problems from different perspectives
Extension questions: 1: Draw diagrams to show the electrons in shells for the following elements: a) magnesium b) nitrogen c) chlorine & d) neon ? 2: Electrons are held in their orbits by the attraction between the negatively charged electrons and the positive nucleus. Explain why more energy is required to remove electrons from the inner shells ? 3: Draw three diagrams to show the electrons in their shells for lithium, sodium and potassium. In a chemical reaction only the outer single electron is transferred. Explain using what you have learn today why potassium is more reactive than sodium ? Know this: a: Know that electrons in the same shell have the same energy level. b: Know that electrons can jump energy levels or shells and when they lose energy they give out packets of light. Friday 21 October 2011 Introduction: Electrons found in the same shell have the same energy level. Electrons can be jump form shell to shell by adding or removing energy. When they move form a higher to a lower energy level, the energy they give out is a packets of light. This gives each element a unique colour spectrum when combusted in air. Carbon has 6 electrons found in two shells, two in the first and four in the second. The energy required to remove each electron increases. C4.7 Electrons in atoms
C4.7 Look at the photograph and information and answer all the questions: During a chemical reaction, only the outer shell electrons are involved. The trend in the size of the atoms of lithium, sodium and potassium are shown. Since all group metals react by transferring their single outer most electron to a non metal like chlorine, potassium is the most reactive since its outer electron is furthest away from the positively charge nucleus All group I metals have one single electron in their outer shell. They react by losing this electron. What would the charge of the metal ions be when this electron is lost ? Predict how many electrons a group Ii element like calcium and a group 7 element like chlorine have in their outer shells ? What two sub atomic particles do you find located in the nucleus of all atoms ? 1 2 3 4 5 6 7 8 9 10 11 Outer shell Middle shell Inner shell Sodium atom Lithium atom Potassium atom Electronic configuration of sodium Key concepts
C4.7 Plenary Lesson summary: nucleus light shells energy Friday 21 October 2011 When combusted each elements produces a unique colour spectra. Many metals including copper, lithium, calcium, sodium and potassium give very bright colours and their compounds are used in fireworks to produce all the wonderful colours that we see. How Science Works: Research into how electronic configuration determine the chemistry of an element and how these configurations are repeated across the first two periods found in the periodic table. Preparing for the next lesson: Electrons are found in distinct _______ that orbit the ______ of an atom. Electrons in the same shell have the same ________. When electrons jump form a higher energy shell to a lower energy shell, the excess energy is given out as ________. This gives each element a characteristic colour spectrum when they are combusted. Decide whether the following statements are true or false : False True 3: The inner electron shell can hold a maximum of 8 electrons ? False True 2: Electrons are either lost gained or shared during a chemical reaction ? False True 1: Group I metals have one single electron in their outermost electron shell ?
C4.8 Electron structure and the periodic table Decide whether the following statements are true or false:
Understand the electronic configuration for the first 20 elements in the periodic table
Understand the electronic configuration elements of the same group
Understand electronic configuration of elements across a period in the periodic table
Friday 21 October 2011 First activity: Draw how the electrons are arranged in the following elements Helium 2,2: Lithium 2,3 and carbon 2,4 and chlorine 2,8,7 ? PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers Literacy: Atom, proton, electron, neutron, electron configuration, elements, electron shells, nucleus, charges and atomic structure. Numeracy: In the firs electron shell a maximum of two electrons are found, in the second a maximum of eight electrons, in the third and maximum eight electrons and in the fourth a maximum of eighteen electrons are to be found. We will focus on independent enquiry and creative thinking.
Extension questions: 1: What are the electron configurations of a) sulphur b) fluorine c) neon and d) magnesium ? 2: The electron configuration of Lithium is 2,1 and the electron configuration of sodium is 2,8 1. predict the electron configuration for potassium ? 3: How many electrons do the halogen like chlorine and iodine have in their outer shell ? 4: The noble gases all have full outer shells which means they do not participate in chemical reactions. Name three noble gases ? Know this: a: Know the electron configuration of the first 20 elements. b: Know that it is the electrons in the outer shell which determines the chemistry of any element. Friday 21 October 2011 Introduction: Electrons are arranged in shells or orbits around the positive nucleus. Electrons start filling the inner shell first. The inner shell contains two electrons. The next two shells each contain eight electrons. The fourth shell can contain up to eighteen electrons. During chemical reactions electrons in the outer shell of an atom get involved in forming new chemical bonds. In any vertical group of the periodic table, the elements have the same number of electrons in their outer shell. This accounts for the similarity in the chemistries of elements found in each group C4.8 Electron structure and the periodic table
C4.8 a Look at the photograph and information and answer all the questions: Look at the periodic table and the information below. What is the connection between the row and the group and the electronic configuration of electrons in the first 20 elements from hydrogen to calcium ? Electrons are found in shells. Elements with three or less electrons in their outer shell are metals, and four or more are generally non metals. Elements that have full shells belong to the noble gases and are stable. Key concepts N 7 14 O 8 16 F 9 Ne 10 Na 11 23 Mg 12 24 Al 13 27 Si 14 P 15 S 16 Cl 17 35 Ar 18 K 19 Ca 20 40 20 28 31 32 40 39 19
C4.8 b Look at the photograph and information and answer all the questions: Understanding how metals like those found in group I react by losing their outermost electron during a chemical reaction can help us understand about reactivity. Rubidium is the most reactive and lithium the least reactive group I metal. This is because as atoms become bigger, the outermost electrons are held less tightly by the positive nucleus. This makes it easier to remove during a chemical reaction. What forces of attraction keep electrons in their electron shells Describe the relative size of the forces of attraction between the nucleus and the outermost electrons of the lithium and rubidium atoms ? Explain why sodium is less reactive than potassium during a reaction with water ? 2,1 2,8,1 Li Na K 2,8,8,1 Rb 2,8,8,18,1 Sodium atom Electronic configuration of group I metals Potassium atom Rubidium atom Lithium atom Key concepts
C4.8 Plenary Lesson summary: atoms reaction shells lost Friday 21 October 2011 From hydrogen the first element to krypton the 36 th element there is a very close connection between the elements position on the periodic table (vertical group and horizontal row) and its electron configuration. How Science Works: Research into slats, how they are formed, some common examples e.g. sodium chloride and their physical and chemical properties. Preparing for the next lesson: In all ________, electrons are arranged in _________ around a central positively charged nucleus. Electrons in the outermost shell are either _______, gained or shared during a chemical ____________. Decide whether the following statements are true or false : False True 3: Electrons have a positive charge ? False True 2: In a covalent bond metals are shared between atoms ? False True 1: Metals lose their outermost electrons during a chemical reaction ?
C4.9 Salts Decide whether the following statements are true or false:
Understand how salts are formed and know some common examples
Understand the properties of salts
Understand how salts in their molten or aqueous sate can conduct electricity
Friday 21 October 2011 First activity: A salt is formed when a metal like sodium reacts with a non metal like chlorine. Name three common salts for example sodium chloride ? Literacy: Salt, cation, anion, ions, crystalline, crystals, solid, sodium chloride, electrolysis, sodium chloride and copper sulphate, Numeracy: Ions found in salts are just one of four main chemical species. These include atoms in molecules, atoms in metals, ions in ionic compounds and ions in solutions PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers We will focus on creative thinking and reflective learning.
Extension questions: 1: name three other common salts for example lithium iodide. 2: In the reaction where sodium metal reacts with chlorine gas, a white crystalline sodium chloride is formed. Compare the properties of the reactants and the products ? 3: In you could see inside a crystal of sodium chloride why would you see alternate sodium and chloride ions ? 4: Sodium chloride has a boiling point of 1465 o C, where as sodium has a b.p of 890 o C and chlorine a b.p of -34 o C Explain why each has different boiling points ? Know this: a: Know how salts are formed by reacting a metal with a non metal. b: Know the chemical and physical properties of salts. Friday 21 October 2011 Introduction: When a non metal reacts with a metal a crystalline salt product is formed. The products formed during the reaction have very different physical and chemical properties when compared to the reactants they were formed form. Sodium chloride a white crystalline salt is a good example of products having very different properties when compare to the reactant they are made from. Sodium is a soft shiny metal and chlorine is a pale green toxic gas C4.9 Salts
Key concepts C4.9 a Look at the photograph and information and answer all the questions: Chlorine is used to dye to bleach and disinfect drinking water. Why is it important to chlorinate our drinking water ? Sodium hydroxide another by product of the electrolysis of salt can break down grease and fats. Name two products where you might find sodium hydroxide ? Electrolysis of sodium chloride solution gives a mixture of hydrogen and chlorine gas and an aqueous sodium hydroxide solution. electrolysis. The demand for chlorine is much larger than the demand for sodium, electrolysis of aqueous sodium chloride is a more important process commercially. Electrolysis of an aqueous NaCl solution has two other advantages. It produces H 2 gas at the cathode, which can be collected and sold. It also produces NaOH, which can be drained from the bottom of the electrolytic cell and sold. Electrolysis of sodium chloride in solution Cathode products Anode products Hydrogen gas (H 2 ) Chlorine gas Cl 2 Sodium hydroxide (NaOH) Sodium chloride NaCl.H 2 O
Key concepts Look at the photograph and information and answer all the questions: Give three uses of salt mine form huge underground deposits like those you see pictured above? What are the risks of working underground salt mines ? Salt extraction in Europe can be traced back 7,000 years into the past. There are large salt deposits around here in the UK huge deposits of salt have been found in Cheshire. The salt is scrapped out by huge machines like the one pictured above. At the end of each shift up to 5,000 tons of impure salt is then ready for transportation, purification and selling C4.9 b Extracting salt from underground salt deposits
Key concepts Look at the photograph and information and answer all the questions: Meats like bacon, pork salami are preserved using both salt (NaCl). The salt prevents most but not all harmful very bacteria like botulism forming on the surface of the meat. Potassium nitrates is now added when only salt was used to preserve bacon, people who are bacon were at risk form botulism. Why is it not a good idea just to use table salt or NaCl to preserve foods like bacon and salami ? What effect does adding salt to meat have and why does this effect help prevent the meat form going off ? C4.9 c NaCl NaCl NaCl Preserving meat using salt (sodium chloride)
C4.9 Plenary Lesson summary: metal conduct sodium charged Friday 21 October 2011 All salts contain a metal and non metal ions which form crystals with regular arrangement of ions. Some salts like sodium chloride are highly soluble whereas others like calcium carbonate are high insoluble. How Science Works: Research into ionic theory, how ions of elements are formed and the ionic bond between metal and non metal ions like sodium chloride. Preparing for the next lesson: Salts like _______ chloride are formed when a _________ and non metal react forming ions of toms. These oppositely _________ ions form salt crystals. Crystalline salts have high melting points are mostly soluble and can ______ a current when molten or in solution. Decide whether the following statements are true or false : False True 3: FeS 2 or iron sulphide is better known as fool’s gold ? False True 2: Some salts like calcium carbonate are insoluble in water ? False True 1: When molten all ionic salts conduct an electrical current ?
C4.10 Ionic theory Decide whether the following statements are true or false:
Understand what an ion is
Understand how ionic compounds are formed
Understand the properties of ionic compounds
Friday 21 October 2011 First activity: Think of what happen to table salt (sodium chloride) when you add it to pure water. What happens to the crystals and the individual sodium and chloride ions ? Literacy: Ions, ionic compounds, anion, cation, positive ions, negative ions, crystal, ionic compounds, metal and non metal. Numeracy: The charge of an ions is determined by the number of electron lost or gained by a metal or non metal atom. Lithium loses one electron to form its ion with a + 1. Fluorine loses one electron to form its ion with a charge of -1. PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers We will focus on taking responsibility, showing confidence in ourselves and our.
C4.10 Ionic theory Extension questions: 1: Explain why solid crystals of salt (sodium chloride) do not conduct electricity ? 2: During the electrolysis of copper chloride solution (CuCl 2 ) containing copper and chloride ions, what would you observe at the cathode (-ve) and the anode (+ve) ? 3: Name three salts of a) sodium b) calcium and c) copper ? 4: Reactive metals are extracted form their salts (compounds) using electrolysis. Name two metals extracted using this method ? Know this: a: Know what an ion is and be able to recall some common examples. b: Know the properties of some common ionic compounds. Friday 21 October 2011 Introduction: A single crystal of any ionic compound or salt contains many millions of positive charge metal ions and negatively charged non metals ions. In sodium chlorine the Na + and Cl - ions are packed closely together unable to move. When sodium chloride is dissolved in water or heated until molten these ions are free to move and conduct electricity. During electrolysis, the positively charged metal ions moves towards the negative electrode (cathode) and the negatively charged non metal ions moved towards the positively charge electrode (anode)
Key concepts C4.10 Look at the photograph and information and answer all the questions: Ions of atoms build crystals. The structure extends itself in all directions, giving the crystal a regular arrangement of ions called a lattice. For sodium chloride, the ions arrange themselves alternatively in all three dimensions. This gives sodium chloride crystals a cubic shape. All ionic solids have similar ionic structures to sodium chloride. Write the formulae of the following ionic compounds a) magnesium chloride b) aluminium oxide c) calcium carbonate and d) copper sulphate ? Explain (looking at the picture opposite) the arrangement of the sodium and chloride ions in sodium chloride ? Which of the following compounds contain molecules and which contain ions a) Octane b) copper oxide c) water d) hydrochloric acid and e) calcium chloride ? Ionic bond between sodium and chloride ions Ionic bond
C4.10 Plenary Lesson summary: ions chloride metal packed Friday 21 October 2011 When sodium chloride is heated to a molten state it will conduct electricity. During electrolysis of molten sodium chloride, the positively charged metal ions move towards the cathode where sodium metal is formed,. The negatively charged chloride ions moves towards the anode forming chlorine gas. How Science Works: Research into ionic theory and atomic structure. Preparing for the next lesson: Ionic compounds consist of ______ and non metallic elements. Sodium ________ crystals contain millions of tiny sodium and chloride _____ oppositely charged which are closely ___ together in a regular three dimensional structure. Decide whether the following statements are true or false : False True 3: All metal ions have a positive charge ? False True 2: Salts when molten can conduct an electrical charge ? False True 1: CaCO 3 and LiBr are both ionic salts ?
C4.11 Ionic theory and atomic structure Decide whether the following statements are true or false:
Understand the difference between ions and atoms of elements
Understand the electron configuration of ions
Understand how to predict the formula of ionic compounds
Friday 21 October 2011 First activity: Here is a list of ions and their relative charges: Na + , Ca 2+ , Al 3+ , Li+ Mg 2+ , Cl - , O 2- , S 2- , & I - ? The overall charge for an ionic compound is zero. Work out the correct formulae for a) Magnesium chloride b) Sodium oxide, c) Aluminium iodide d) Lithium sulphide and e) Aluminium oxide PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers Literacy: Ions, ionic compounds, anion, cation, positive ions, negative ions, crystal, ionic compounds, metal, non metal ionic theory and formula. Numeracy: The overall charge of an ionic compound is always zero. This means that the sum of the charge of the metal and non metal ions must always be zero in a compound. This law determines the ratio of metal (+ve) and non metal (-ve) ions in a compound. We will focus on creative thinking and exploring possibilities
Extension questions: 1: In the following metals state how many electrons are lost and the charge on the ion formed a) Na b) Ca c) Mg d) Li and e) Al ? 2: In the following non metals state how many electrons are gained and the charge on the ion formed a) Cl b) O c) S d) F e) I? 3: Write the electron configuration of the following a) sodium atom and ion b) Chlorine atom and ion c) Calcium atom and ion and d) Oxygen atom and ion ? 4: Give the formula of a) Calcium chloride b) Magnesium oxide c) Aluminium oxide and d) Sodium oxide ? Know this: a: Know the electronic configuration of ions of atoms. b: Know how to predict the formula of ionic compounds. Friday 21 October 2011 Introduction: TExplaininh how atoms of like sodium and chlorine elements change into ions of elements requires us to understand that all elements prefer the same electron configuration as the noble gases. In metals like sodium, they lose electrons forming positive ions gaining empty outer shells. In non metals like chlorine they gain electrons forming negative ions gaining full outer shell. C4.11 Ionic theory and atomic structure
Look at the photograph and information and answer all the questions: The charges of ions of elements in the periodic table follow a strict pattern. All group one elements have ions with a charge of +1. All group 2 elements have ions with a charge of +2 and all group 3 elements have ions with a charge of +3. In group 5 elements have ions with a charge of -3, group 6 elements have ions with a charge of -1 and group 7 elements have ions with ions a charge of -1. Group four elements have two electrons to lose or gain so do not form ions and group 8 elements are stable and do not form any compounds. Explain why a) all group one elements form ions with a charge of +1 and b) group four elements cannot form ions during a chemical reaction ? Using the tables opposite left predict the formula of a) Lithium oxide b) Magnesium chloride c) Aluminium chloride ? 1 2 3 4 5 6 7 8 Na Mg Al Si P S Cl Ar Li C N O F Ne group element ion Li C N O F Ne Na Mg Al Si P S Cl Ar + -3 -2 -1 + +2 +3 -3 -1 -2 Ions of atoms in the periodic table Compound Magnesium oxide Mg 2+ O 2- MgO Lithium Oxide Li +1 O 2+ ………. Calcium chloride Ca 2+ Cl - CaCl 2 .......................... Mg 2+ Cl - ………. Aluminium oxide Al 3+ O 2- Al 2 O 3 .......................... Al 3+ Cl -1 …….. +ve ions -ve ions Formula C4.11 Key concepts
C4.11 Plenary Lesson summary: metal ions stable trnasferred Friday 21 October 2011 Metal ores like aluminium oxide (bauxite) and titanium dioxide are simply ionic compound containing metal and non metal ions that are very stable. In order to reverse the transfer of electrons form metal to non metal electrical energy has to be used during the electrolysis of the molten ore. This is how reactive metals are extracted form their ores using electricity. How Science Works: Research into different chemical species a) atoms in metals b) atoms in molecules c) ions and d ions in solution. Preparing for the next lesson: When metals and non metals react they form _____. Electrons are lost from ______ atoms and _________ to non metal atoms Ions are _______ because they have the electronic configuration of a group 8 noble gas. Decide whether the following statements are true or false : False True 3: Oppositely charged ions form regular crystals structures ? False True 2: The formula of lithium chloride is LiCl 2 ? False True 1: All group one ions have a charge of -1 ?
C4.12 Chemical species Decide whether the following statements are true or false:
Understand the nature of atoms, molecules, ions and ions in solution
Understand the nature of different chemical species
Friday 21 October 2011 First activity: Give one example of the following a) ionic compound b) covalent compound, c) Pure metal d) Solution containing water and an ionic solute and e) an alloy of two metals ? Literacy: Atoms, elements, molecules, ions, metallic structure, covalent molecules ionic compounds, solutions and chemical species . PLTS Independent enquirers Creative thinkers Reflective learners Team workers Effective participators Self managers Numeracy: Ions found in salts are just one of four main chemical species. These include atoms in molecules, atoms in metals, ions in ionic compounds and ions in solutions We will focus on being creative thinkers and effective participators.
C4.12 Extension questions: 1: Explain why the properties of sodium chloride (NaCl) are very different from the properties of chlorine (Cl 2 ) and sodium (Na) ? 2: Give the name and formula or symbol in the following a) lithium chloride b) copper iodide c) Magnesium oxide d) bromine e) sodium f) Iron sulphide ? 3: Name four chemical species found in the human body, for example water (H 2 O) ? 4: Using your knowledge of electron theory explain why sodium and chlorine are reactive where as ions of sodium and chlorine are not ? Know this: a: Know the nature of atoms, atoms in metals, ions, ions in solutions and atoms bonded together in covalent compounds. Friday 21 October 2011 Introduction: The same element can exist as atoms, ions in ionic compounds or solutions, bonded to other atoms in covalent compounds. Chemists describe these different forms as chemical species. Atoms in metals: metallic atoms in regular arrangement, some metals like sodium are very reactive some like gold are very un reactive Atoms in molecules: oxygen (O 2 ) and water (H 2 O) are simple molecules where atoms are joined together in by covalent bond Ions in ionic compounds: Sodium chloride consists o sodium and chloride ions. These ions are oppositely charge and quite un reactive Ions in solutions: When sodium and chloride ions are dissolve in water they form a salt solution. The slightly charge water molecules surround each ion and solvate (dissolve) them forming a solution Chemical species
C4.12 a Look at the photograph and information and answer all the questions: There are four main types of chemical species. Atoms in metals, atoms in molecules, ions and ions in solution. The properties of these species differs because of their different electronic configurations. Or example chlorine atoms in chlorine molecules are very reactive where as ions of chorine atoms are very un reactive Sea water contains many different chemical species. List three chemical species that sea water would contain ? Explain the difference of electronic configuration between a atom of chlorine and an ion of chlorine ? Explain how water dissolves ions like sodium ions and chloride ions ? Atoms in metal Ions in solution Ions in ionic compound Atoms in molecules Key concepts
C4.12 b Look at the photograph and information and answer all the questions: A compound contains two or more types of atoms joined together by a chemical bond. The particles in a compound are known as molecules. Compounds always have a formula which tells us which and how many elements they are made from. There are millions of compounds all made from elements found in the periodic table. Give the correct names of compounds when the following substrates react with one another a) sodium and chlorine b) iron and sulphur c) magnesium and oxygen ? Both bones and teeth made from calcium carbonate with the formula CaCO 3 . Using the formula, what elements does the compound calcium carbonate contain ? Look at the two pictures opposite…which picture describes ‘a mixture of compounds and elements’ and which picture describes ‘molecules in a compound’ ? water methane glucose H 2 O CH 4 C 6 H 12 O 6 Key concepts
C4.12 Plenary Lesson summary: molecules atoms electronic solutions Friday 21 October 2011 Understanding how to name and identify different chemical species is important when trying to understand the different properties of metals, ions, molecules and solutions. How Science Works: Revise for your end of module test. Preparing for the next lesson: There are four main chemical species: ______ in metals, atoms in _________ ions and ions in ____________. Their properties differ because of the differing _________ configurations. Decide whether the following statements are true or false : False True 3: Ions are reactive because they have electron configuration of a noble gas ? False True 2: Reactive metals lose electrons during chemical reactions ? False True 1: A solution of sodium chloride contain three different chemical species ?