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1. Slide 1: Science Interactive LTD Copyright 2005 Science Interactive LTD Science base multimedia CD-ROM for PC is a collection of 38 units or tools totalling over 1150 PowerPoint slides. Each unit covers a wide range of different delivery and learning styles, offering an exciting way to involve your pupils during lessons or revision sessions. All styles of teaching and learning are supported through use of high quality images, graphics, challenging exercises and questions. Units can be used in the classroom via an interactive whiteboard, data projector or used during individual study via a PC or school network. Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: sales@science-interactive.co.uk web: www:science-interactive.co.uk Unit 1: The Digestive System Unit 20: Crude Oil and its Products Unit 2: The Circulatory System Unit 21: Rock Cycle Unit 3: Healthy Body and Immunity Unit 22: Elements, Molecules and Compounds Unit 4: The Respiratory System Unit 23: Ionic and Covalent Compounds Unit 5: Nervous System and the Senses Unit 24: The Halogens, their Uses and Compounds Unit 6: Human Homeostasis Unit 25: The Noble Gases, their Properties and Uses Unit 7: Hormones and the Endocrine System Unit 26: Rates of Reaction Unit 8: Drugs and Bad Body Maintenance Unit 27: Energy Unit 9: Photosynthesis in Green Plants Unit 28: Generating Electricity and its Domestic Use Unit 10: Water Transport in Plants Unit 29: Electricity Unit 11: Flow of Energy and Elements through the Environment Unit 30: Light and the Electromagnetic Spectrum Unit 12: Mitosis and Meiosis Unit 31: Radioactivity Unit 13: Inheritance and Selection Unit 32: Newton's Forces and the Effects of Forces Unit 14: Evolution and Human Impact Unit 33: Earth and Space Unit 15: Genetic Engineering Unit 34: The Earth and Plate Tectonics Unit 16: The Periodic Table and its Elements Unit 35: The Alkaline Earth Metals Unit 17: The Alkali Metals Unit 36: Sound and Hearing Unit 18: Metals and their Properties Unit 37: Natural Forces Unit 19: The Transitional Metals Unit 38: Cells, Tissue, Organs and Organs systems
2. Slide 2: Science Interactive LTD Copyright 2005 7 Li 3 19P+ 3P+ 20N 4N 23 Na 3E- 19E- 11 Lithium Potassium 39 K 11P+ 19 37P+ 12N 48N 11E- 85 Rb 37E- 37 Sodium Rubidium Unit 17  The Alkaline Metals 
3. Slide 3: Unit 17: The Alkaline Metals Science Interactive LTD Copyright 2005 Understand: Keywords: Alkaline, Metals, Lithium, Sodium, Potassium, The physical and chemical properties of the 1. group I elements, the alkaline metals. Rubidium, Caesium, Physical, Chemical, That they have similar chemical and physical 2. Properties, Ionic, Compounds, Non metals, properties based on their electronic Ions, Reactions, Oxides, Hydroxide, Halides, configuration. Atoms, Chemical, Bond & Reactivity. Their reactions and compounds with oxygen. 3. Their reactions and compounds with water. 4. Their reactions and compounds with the 5. halogens. That their reactivity increases as you descend 6. the group. That the alkaline metals react with other non 7. metals during the formation of ionic compounds That the electrolysis of sodium chloride yields 8. sodium metal and chlorine gas. Click mouse to begin Science Interactive LTD PO BOX 50764 LONDON NW6 9AT web: www.science-interactive.co.uk email: sales@science-interactive.co.uk
4. Slide 4: Science Interactive LTD Copyright 2005 Physical properties of the alkaline metals one Group I of the periodic table contains a family of very reactive metals known as the alkaline metals. This group of e________ contains lithium, sodium, potassium and rubidium. They are not found in their pure state like gold, but are found tied up in ionic compounds. These metal elements have relatively low melting or boiling points and densities, when compared to transitional m______ like copper, iron and titanium. Name two compounds that contain sodium and potassium ? The alkaline metals: Word bank: elements metals Position of the alkaline metals The alkaline metals Diagram Li Na K Rb 3 11 19 37 Found in group I of the periodic table, all The alkaline metals have similar chemical properties Notes the alkaline metals have one electron in because they all have one electron in their outer shell. their outermost shell. Losing this single Their reactivity and atom size (radius) increases as electron to other non-metal atoms you descend the group from lithium to rubidium. completely empties their outer shell Their melting and boiling points rise as you descend making the ion of the atom stable. the group.
5. Slide 5: Science Interactive LTD Copyright 2005 Physical properties of the alkaline metals two The group I elements, the alkaline metals are all reactive metals able to form ionic compounds with other non-metals like chlorine. They have similar p_______ and chemical properties. They all have a typical shiny metallic appearance when freshly cut, but all tarnish within minutes of contact with air. They all have to be stored under o____ so they don’t react with either oxygen or water vapour. Like all metals, they are good conductors of heat and electricity, but they have low melting and boiling points. Give a definition of an ionic and covalent compound ? Physical properties of group I alkaline metals: Word bank: physical oil Element Symbol Formula Atom Electron configuration Shared group I properties All are reactive metals, Lithium Li 2,1 tarnish in air and have to be Li 3 Li Be Li Be Li Be stored under oil. All form ions carrying a +1 plus charge Li+, Na+, K+ Sodium Na Na 2,8,1 All are less dense than water 11 Na Mg Rb Na Mg and react vigorously to form Rb hydroxides with alkaline pHs. Na Mg Rb Potassium K K All react with non-metals to 19 2,8,8,1 form ionic salts with similar K Ca formulas (e.g. Lithium Li Be K chloride LiCl) Ca Rubidium Sr Rb All are soft and can be cut Rb 37 2,8,8,18,1 with a knife. Na Mg Rb Sr K Ca
6. Slide 6: Science Interactive LTD Copyright 2005 Properties and uses of lithium Lithium is a shiny soft reactive metal. Lithium is the least reactive group I metal. Lithium compounds are found in a wide range of uses including long life batteries, similar to those used in pacemakers. Lithium is also used in psychiatric drugs to control the behaviour of patients suffering from aggressive psychosis. Lithium reacts readily with o_______, water and acid forming ionic salt compounds which are white, alkaline and highly soluble. Lithium gives a r____ flame when combusted in oxygen Find out about other uses of lithium or its compounds ? Properties and uses of lithium: Word bank: oxygen red Lithium Metallic structure Lithium batteries Anti psychotic drugs Li Na K Rb 3 11 19 37 Lithium is a shiny silver metal, which Lithium is the least reactive group I alkaline metal. Lithium is easy to cut with a low density. compounds have many uses including batteries found in mobile Atoms are held in a metallic structure. phones, calculators and heart pacemakers. Lithium is also used as Lithium is a good conductor of heat an antipsychotic drug. It has an effect in the human body to lower and electricity. The symbol of lithium the activity of the brain and is often called a chemical is Li. straightjacket.
7. Slide 7: Science Interactive LTD Copyright 2005 Properties and uses of sodium Sodium is a shiny soft reactive metal. Sodium is the second least reactive group I metal. Sodium compounds are found in a wide range of chemicals or uses including sodium found in table s_____ or sodium chloride. It is also used in ‘sodium vapour lights’ found in street lighting. Sodium reacts readily with oxygen, water and acid forming ionic salt compounds which are white, alkaline and highly soluble. Sodium gives an o_______ flame when combusted in oxygen. Find out about other uses of sodium or its compounds ? Properties and uses of sodium: Word bank: salt orange Sodium Metallic structure Sodium vapour lamps Sodium in sodium chloride Na K Rb 11 19 37 Sodium is a shiny silver metal, which Sodium is the second most reactive group I alkaline metal. is easy to cut with a low density. Sodium is used in sodium vapour lights. This characteristic Atoms are held in a metallic structure. orange light helps light our streets at night. Sodium is also found Sodium is a good conductor of heat in table salt or sodium chloride. Too much salt in our diets will and electricity. The symbol of sodium lead to high blood pressure and the increased risk of is Na. cardiovascular disease.
8. Slide 8: Science Interactive LTD Copyright 2005 Properties and uses of potassium Potassium is a shiny soft reactive metal. Potassium is the third most reactive group I metal. Potassium compounds are found in a wide range of chemicals or uses including soluble potassium ions essential for healthy p______ growth. Potassium reacts readily with oxygen, water and acid forming ionic salt compounds which are white, alkaline and highly soluble. Potassium gives a l_______ flame when combusted in oxygen. Find out about other uses of potassium or its compounds ? Properties and uses of potassium: Word bank: plant lilac Potassium Metallic structure Potassium in fertilisers Potassium in bananas K Rb 1 19 37 Potassium is a shiny silver metal, Potassium is the third most reactive group I alkaline metal. It is which is easy to cut with a low available in schools and needs to kept under oil in a locked metal density. Atoms are held in a metallic cabinet. Potassium is found in fertilisers, and is used by plants for structure. Potassium is a good healthy growth. Without potassium, plants would have yellow conductor of heat and electricity. The leaves and stunted growth. Bananas are also rich in potassium and symbol of potassium is K. are good for you.
9. Slide 9: Science Interactive LTD Copyright 2005 Properties and uses of rubidium Rubidium is a shiny silver soft reactive metal. Rubidium is the most reactive and dangerous group I metal. It is so reactive that schools cannot use it in their laboratories. Rubidium compounds are found in a wide range of chemicals or uses including rubidium used in psychiatric drugs to control the behaviour of patients suffering from aggressive psychosis. Find out about any other uses of rubidium ? Properties and uses of rubidium: Rubidium Metallic structure Mental illness in Humans Sedative Drugs and rubidium Rb 37 Rubidium is a shiny metal which is a Rubidium is the most reactive and dangerous of the group I liquid at room temperature. Atoms are alkaline metals. It is so reactive that schools cannot use it in their held in a metallic structure. Rubidium laboratories. It is kept in sealed vials to prevent it making contact is a good conductor of heat and with oxygen or water. Rubidium, like lithium is found in strong electricity. The symbol for rubidium sedative drugs like valium and librium. These drugs have a is Rb. sedative effect on the patient, reducing anxiety and stress.
10. Slide 10: Science Interactive LTD Copyright 2005 Detecting the presence of group I metal compounds When compounds like sodium chloride are heated in a gas flame they give a characteristic colour. We can take a compound and identify which group I metal the compound contains by its colour and light spectrum. For example sodium in sodium chloride gives a distinctive orange colour in a blue gas flame. Give the colour of copper and magnesium in oxygen ? Metal flame tests: Metal Potassium Sodium Lithium Rubidium Flame test Spectrum When combusted in When combusted in When combusted in When combusted in Notes oxygen, potassium oxygen, sodium gives a oxygen, lithium gives a oxygen, rubidium gives a characteristic characteristic orange characteristic deep red gives a characteristic lilac flame. flame. flame. red -orange flame.
11. Slide 11: Science Interactive LTD Copyright 2005 Group I alkaline metals with oxygen All the elements found in group I can readily form metal oxides with the element oxygen. During the reaction, group I metals lose one electron to oxygen. This group of ionic compounds includes sodium oxide. The group I oxides are all soluble and mostly white crystalline solids. Example 4Na + O2 (g) 2Na2O (s) (s) Group I metals with oxygen: Li Na K Rb Group 3 11 19 37 O2 Aluminium + Chlorine Lithium Oxygen Lithium oxide (Li2O) - + Example one 2- 2- + H O O Be MgLi Be O Mg Li Li Be O Li Be x2 ++ - + +2 2- 2- Example two H O O Na Mg - Mg OMg Mg Na O Mg Rb Na Na Mg Ne Rb x2 Sodium Oxygen Sodium Oxide (Na2O)
12. Slide 12: Science Interactive LTD Copyright 2005 Group I alkaline metals with water All the elements found in group I can readily form metal hydroxides with the water molecule. During the reaction, group I metals lose one electron to the forming hydroxide ion. This group of ionic compounds includes sodium hydroxide. The group I hydroxides are all soluble and mostly white crystalline solids. Example 2Na (s) + 2H2O (g) 2NaOH (aq) + H2 (g) Group I metals with water: + Li Na K Rb Group 3 11 19 37 O O Li Be Li Be H H H H H20 Aluminium + Chlorine + +2 Lithium hydroxide (LiOH) Lithium Water - H + Example one Na Mg Na Mg O O Rb H H H H H OBe O Li Be CLi H H S O H H - H + - + + F H Example two H O K K O - H C H Ca Na Mg Na Mg - Rb S O - H H H Potassium Water Potassium hydroxide (KOH) O O O F Sr
13. Slide 13: Science Interactive LTD Copyright 2005 Reactivity of the group I metals The alkaline metals become more reactive as you descend the group, for example reactions between sodium and lithium with oxygen or water are moderately fast. Reactions with potassium and oxygen or water are very fast. Reactions between rubidium and oxygen or water are explosive. The reason why rubidium is the most reactive group I metal is because, as the size of the atom increases, less energy is required to lose the outer electron during the formation of ionic compounds. What's the rule for the group VII elements, the halogens ? Reactivity in metals: Reactivity Reactivity of the group I alkaline metals _ _ _ _ Lithium Sodium + + + + Potassium Rubidium Lithium Sodium Potassium Rubidium Lithium reacts with Sodium reacts with Potassium reacts with Rubidium reacts with acid. Displacement from with oxygen, water and Behaviour of elements Li Na K Rb (on heating) oxygen, (on heating) oxygen (on heating) oxygen (on heating) oxygen 3 11 19 37 cold water and HCl and cold water and and with cold water and with cold water acid (moderately fast.) HCl acid (very fast.) and HCl acid and HCl acid their compounds. Displaced from its Displaced from its (Violent) Displaced (Explosive) Not compounds by Na, K compounds by K & from its compounds displaced from its & Rb. Rb. by Rb. compounds. All the alkaline metals from group I are extracted from their ionic compounds using electrolysis. Unlike iron and copper they cannot be displaced from their ores using carbon.
14. Slide 14: Science Interactive LTD Copyright 2005 Properties of group I ionic compounds Ionic compounds of the group I metals are all strongly alkaline. Based on the chemistry of their ionic bond, these compounds have similar properties. Mostly, they are highly soluble in water and have a crystalline structure under the m__________. Group I ionic compounds like sodium chloride are white in colour. They also conduct electricity when molten or in solution. They also have very high m__________ points, for example sodium chloride becomes molten at temperatures in excess of 1000oC. General properties of ionic compounds: Word bank: microscope melting Property one Property two Property three Property four Property five Chlorine gas Anode NaCl Molten Molten Sodium Sodium Cathode Property one: The majority of group I ionic compounds are white in colour. Some ionic compounds are coloured, for example copper sulphate is a deep blue colour. Property two: They form regular crystals and appear like mini diamonds under the microscope. Property three: They have very high melting and boiling points due to the very strong forces of attraction between the ions. Property four: When molten or in ionic solutions, ionic compounds can conduct electricity. Property five: They are highly soluble in water.
15. Slide 15: Science Interactive LTD Copyright 2005 Group I metal halide compounds All the elements found in group I can form metal halide compounds with the halogens. During the reaction, group I metals lose one electron to the halogen element. This group of ionic compounds includes sodium chloride. They are all soluble and mostly white crystalline solids. - Draw a dot and cross diagram F NaI. for Example 2Li (s) + Cl2 (g) 2LiCl (s) Group I metals with the halogens: F The Alkaline Metals H He The Alkaline Earth Metals + 1 2 Metals - F Cl Br I Se mi Metallic Elements I II III IV V VI VII VIII Non -Metals - Li Be B C N O F Ne Group The Halogens 9 17 35 53 3 4 5 6 7 8 9 10 The Noble Gases Na Mg Al Si P S Cl Ar Li Be 12 11 13 14 15 16 17 18 LiTi Ni Be K Ca Kr Br I Sc V Cr Mn Fe Co Cu Zn Ga Ge As Se Br 19 20 36 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 Br Rb Sr Xe Y Zr Nb Tc Ru Rh Pd Ag Cd In S Sb Te I Mo 37 38 42 54 39 40 41 43 44 45 46 47 48 49 50 51 52 53 Cs Ba Au Hg La Hf Ta W Re Os Ir Pt Ti Pb Bi Po At Rn Fluorine Chlorine 55 56 79 80 57 72 73 74 75 76 77 78 81 82 83 84 85 86 Aluminium + Chlorine + Fr Ra +2 87 88 Lithium Chlorine Lithium Chloride (LiCl) - + Example one Na Mg - Na Mg Rb Cl Li Be Li Be Cl Cl F F Cl Cl - + + + Example two Br Br I K K Na Mg Ca Na Mg Rb - Potassium bromine Potassium bromide (KBr) Sr
16. Slide 16: Science Interactive LTD Copyright 2005 Rules for group I ionic compounds There are several rules, that help you to understand what happens to the atoms and their electrons during the formation of group I ionic compounds. Remember for atoms to be stable, they either need to lose of gain electrons to empty or f____ their outer shells therefore having the same electronic configuration as the noble gases. Ions of atoms are very stable and once formed do not easily revert back to their a________ electronic configuration. That’s why we have so many compounds and very few elements found in their natural state. Group I ionic compounds and their rules: Word bank: fill atomic Rule one Rule two Rule three Rule four and five - + Na Cl Na Cl Na Cl Ionic Bond Rule One: Ionic compounds contains a metal and non-metal. Rule two: Group I metals always lose one electron forming a +1 positive ion. Rule three: Non metals always gain this electron forming negative ions. Rule four: The attraction between the positive and negative ions is the ionic bond. Rule five: The overall charge of an ionic compound must always equal zero.
17. Slide 17: Science Interactive LTD Copyright 2005 Building ionic crystals Ions of atoms build crystals. The structure extends itself in all directions giving the crystal with a regular arrangement of ions called a l________. For sodium chloride, the ions arrange themselves alternatively in all three dimensions. This give sodium chloride crystals a c_______ shape. All ionic solids have similar ionic structure to sodium chloride. Did you know you can grow your own crystals using a small seed crystal and a saturated ionic solution...it takes about a week ! Ionic crystals: Word bank: lattice cubic Sodium chloride Simple unit Crystal structure Diagram - + 2+ 2- Cl- Cl- Na Cl O Mg Na+ Cl- Cl- Diagram Sodium chloride: Ions of sodium and chlorine have opposite charges. Simple unit: The attraction between the sodium ion and the chloride ions form a single unit. Ions begin to build 3-D shapes in a regular shape. Crystal structure: Thousands of ions arrange alternatively to form salt crystals.
18. Slide 18: Science Interactive LTD Copyright 2005 Electrolysis of brine sodium chloride Chlorine and its compounds are used in huge quantities around the world. Chlorine is extracted from sodium chloride using electrolysis. During e____________, the sodium ion regains its single electron forming the metal sodium. Conversely, the chloride ion loses its electron to form molecular chlorine gas which is then captured at the anode. Equation: Cathode: 2Na+ + 2e- 2Na Anode: 2Cl- Cl2 + 2e- Electrolysis of sodium chloride: Word bank: electrolysis Electrolysis of sodium chloride What happens during the electrolysis of sodium chloride Chlorine gas Li Na K Rb Anode 3 11 19 37 NaCl Molten Molten Sodium Sodium Cathode Cathode (-ve) Anode (+ve) Sodium (Na+) ions when Chloride (Cl-) ions when molten Concentrated sodium chloride or brine is molten are free to move. The are free to move. The chloride ions sodium ions being positively being negatively charged travel to added to the electrolysis cell. This is charged travel to the negative the positive anode. Chloride ions heated and allowed to become molten. cathode and regain their lost (Cl-) lose their electron and form The current is then switched on and electron. Molten sodium is diatomic chlorine (Cl2.) Chlorine is electrolysis starts. formed at the cathode. then used as a gas.
19. Slide 19: Science Interactive LTD Copyright 2005 Extension questions and homework 1: Define the following terms: Metals, Elements, Ionic-compound, Ion & Ionic-bond. 2: Look at the three pictures below. Complete the table. Picture Element Physical properties of metals and their main uses One Lithium Two Sodium Three Potassium 3: Answer the following: a) Why are the group I metals known as the alkaline metals. 23 b) Sodium has this chemical symbol; What does all this information mean. Na c) Draw an atom of sodium from the information given. 11 d) In part C, you drew an atom of sodium, now label the protons, electrons and neutrons. e) Name three compounds in which an alkaline metal can lose an electron to form an ion. f) Give five properties of all metals. How do the chemical and physical properties of the alkaline metals differ from an average transitional metal like copper, gold or iron. g) All the alkaline metals have a metallic structure, explain this term.
20. Slide 20: Science Interactive LTD Copyright 2005 4: Complete the following table. Group I metal Electrons in outer shell State at room temperature Colour Symbol Lithium 1 Li Sodium Solid Potassium 5: Answer the following questions: a) The chemical reactivity of the alkaline metals increases as you go down the group: Explain why. b) The boiling and melting points of the alkaline metals decrease as you go down the group. Explain why. 6: Complete the following table. Name the salts formed during the following reactions. Reactants Salt Formula Reactants Salt Formula Lithium + Chlorine Lithium + Fluorine Sodium + Water Sodium hydroxide Sodium + Chlorine NaCl Potassium + Chlorine Potassium + Water + 7: Draw a dot and cross diagram for LiI, NaOH & Na2O Li Be LiI NaOH Na2O - + +2 H O O Na Mg Rb Ca - Internet: F + Go to google.co.uk and find out the use of sodium hydroxide and sodium chloride. How do they extract sodium chloride from the brine pits found in Cheshire. K -