Knox Academy S3 Chemistry

Transcription

1 Knox Academy S3 Chemistry Unit 2: Atoms and Ions Pupil Write-on Booklet Pupil Name: Class: 1

2 Lesson 1: Pictures of Atoms In 1800 John hard _. described atoms as small, solid, In 1911 Ernest described atoms as being made up of small charged particles occupying a volume of _ space. Rutherford fired radioactive particles at a thinn sheet of foil. Most of the radioactive particles passed straight through the _ foil. Some changed direction ( _) Very few bounced back ( _) 2

3 Summary: Most of the mass of an atom is concentrated inn a small area known as the _. The nucleus has a positive charge deflecting other positively charged particles (like charges _). Most of an atom is _ space occupiedd by fast moving negatively charged electrons. Lesson 2: Structure of an Atom Rutherford describedd atoms as mostlyy with a solid core calledd the nucleus. _ space He described most of the mass of an atom a being concentrated within the _. Atoms are made up off three different types off subatomic particles electrons, _ andd neutrons. Electrons: Have Have a charge virtually mass. (-1). 3

4 Are found around the nucleus. Are organised in levelss or dependind ng on the amount of that they contain Protons: Have Have _ a charge a mass of _ atomic mass _ move. (+1) unit (a.m.u.) Are located in the _. Neutrons: Have overall charge are neutral Have a mass of _ atomic mass unit (a.m.u.) Cannot. Are located in the. Rutherford s Model of a Helium Atom: 4

5 Atoms are electrically _ they contain equal numbers of positive and negative charges. Atoms therefore contain the number of positive protons as negative electrons. No. of _ = No. of electrons The number of protons found in the nucleus of an atom is the same as the element s number. If we change the number of protons we are changing the of element. The protons and neutrons of an atom make up _ of the atom s physical mass. Mass number = no. _ + no. neutrons Summary: Particle Location Charge Mass Proton Neutron Electron No. of protons = number of element No. of protons = no. of _ number = no. of protons + no. neutrons 5

6 Lesson 3: Atomic Mass _ notation is used to show information about an atom: number e.g. 7 Li 3 of element number Atoms of the same element may contain different numbers of. This gives rise to atoms with different numbers. are atoms of the same element that have different mass numbers. Isotopes contain the number of protons, but different numbers of neutrons. Due to isotopes, we record the _ atomic mass for an element. A data booklet shows the atomic masses of selected elements. The relative atomic mass is a average of the atomic masses of all the isotopes present. 6

7 Name No. Protons No. Neutrons No. Electrons Hydrogen Helium Lithium Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Relative Atomic Mass Calculation: 7

8 Summary: _ contain the electrons. particles protons, neutrons and All the atoms of the same element contain the number of _. same Isotopes are atoms off the same element whichh contain different numbers of._ Isotopes have different numbers. Relative Atomic Mass gives the weighted atomic mass for an element. _ Lesson 4: Electronic Arrangements Electrons orbit the _. Most of the volume off an atom is _ space. Electrons are organised into levels or something like the layers in an onion. The electrons closest energy. to the nucleus have the The electrons furthest out from the nucleus n have the _ energy. 8

9 The 1 st energy level orr shell can hold upp to _ electrons. The 2 nd energy level orr shell can hold up u to _ electrons.. The 3 rd energy level orr shell can hold up u to _ electrons.. The energy shells fill in order, from _ sts to _ rd. A data booklet shows the electron arrangements of the elements found in groups _ to _. Element Total No. 1 st 2 nd 3 rd 4 th Electron Electrons Shell Shell Shell Shell Arrangement H He Li Be B C 9

10 Element Total No. 1 st 2 nd 3 rd 4 th Electron Electrons Shell Shell Shell Shell Arrangement N O F Ne Na Mg Al Si P S Cl Ar K Ca Draw a target diagram for 2 selected elements: 10

11 Summary: Electrons are organised in levels or like the layers of an onion. The shells fill from the _ out. The further away from the nucleus the the energy of the electron. The electron arrangement for an atom tells us how many _ are contained in each shell. Lesson 5: Outer Electrons The electron arrangement for a calcium atom is _,_,_,_. Draw a target diagram for a Calcium atom. The outermost energy level contains electrons. 11

12 The electrons on the outermost energyy level off an atom can interact with other atoms to form _. The outermost electrons of an elementt determine the properties of the element. The electrons contained in the inner energy levels of an atom cannot interact with other atoms. Thesee electrons form the of an atom. Elements in the same group of the periodic table have _ chemical properties. Elements in the same group of the periodic table have the number of outer electrons. Only _ electrons can interact with w other atoms. The number of outer electrons in an atom determines the properties of that atom. 12

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14 Summary: The _ electrons of an atom determine how it interacts with other atoms. Elements in the group of the periodic table have the same number of outer electrons. Elements in the same group of the periodic table react in a _ way. Lesson 6: Electricity and Compounds Compounds can be divided into 1 of two groups depending on the elements they are made up of. A compound made up of only non-metal elements is said to be. A compound made up of a metal element and at least one non-metal element is said to be _. Name Formula Ionic/ Covalent Lead (II) Bromide Candle Wax Solid Liquid 14

15 Draw a sectional diagram of the apparatus used, below. Covalent compounds do not _ electricity as a solid, liquid or gas. Ionic compounds _ electricity only when present as a liquid, but not as a solid. State symbols can be used to display information regarding the state of a compound. Solid (_) Liquid (_) Gas (_) Aqueous solution ( ) Hexane ( ) Hexane ( C C 6 H 14 ( _) C 6 H 14 (_) 15

16 Summary: Covalent compounds contain only _-metal elements. Covalent compounds do _ conduct electricity regardless of physical state. Ionic compounds contain a _ element and at least one non-metal element. Ionic compounds conduct electricity only when or dissolved in solution. We can use state symbols to show the physical state of a substance solid (_), liquid (l), gas (_) and dissolved in solution ( ). Lesson 7: Compounds and Conduction Ions of an element are formed from _ of the same element. When a metal atom forms an ion it _ its outer electrons to achieve a full outer energy level. A metal atom is _. When it loses electrons to form an ion it is losing negative charges. Metal ions therefore have a charge. Sodium Atoms: Number of protons 11 Number of electrons 11 Electron arrangement 2,8,1 16

17 Symbol Na Sodium Ions: Number of protons Number of electrons Electron arrangement Symbol _, Metal ions have the same electron arrangement as the Noble Gas from the period of the Periodic Table. The number of charges found on a metal ion is the same as its _. When a non-metal atom forms an ion it _ electrons to achieve a full outer energy level. A non-metal atom is _. When it gains electrons to form an ion it is gaining negative charges. Non-metal ions therefore have a charge. Chlorine Atoms: Number of protons Number of electrons Electron arrangement _, _, _ 17

18 Symbol Chloride Ions: Number of protons Number of electrons Electron arrangement _, _, _ Symbol _ Non-metal ions have the same electron arrangement as the Noble Gas from the period of the Periodic Table. The number of charges found on a non-metal ion is the same as its _. Ion Model: Metal and non-metal ions have charges. Opposite charges are _ towards each other. Like charges _ each other. This leads to the creation of an alternating pattern of positive and negative ions in a special structure called a _. In a lattice structure no charged ions touch. Only charged ions touch each other. 18

19 When present as a solid ions are in a fixed position unable to. When melted, the ions are _ from their fixed positions and are then able to move. For compounds to conduct electricity they must contain charged particles ( ) that are able to move. Metal atoms electrons to form positive ions. Non-metal atoms electrons to form negative ions. In an ionic compound, alternating ions arrange themselves to form a _. When held in a lattice, ions cannot and cannot conduct electricity. If melted or dissolved in water the ions are to move, and the substance can conduct electricity. Summary: Metal atoms electrons to form positive ions. Non-metal atoms electrons to form negative ions. In an ionic compound, alternating ions arrange themselves to form a _. When held in a lattice, ions cannot and cannot conduct electricity. If melted or dissolved in water the ions are to move, and the substance can conduct electricity. 19

20 Lesson 8: Solutions and Conductionn Covalent solutions contain freee _ suspended amongst the solvent molecules. Ionic solutionss containn free able a to move through the solvent molecules. Covalent molecules aree _, whilst w ions are charged. Charged particles thatt are able to through a solution allows the solution to conduct electricity. 20

21 Conductivity of an Ionic Solution: No. drops of sodium chloride solution Electrical Current (ma) Draw a line graph of your results and staple it into your booklet here. Silver chloride would not give the same shape of graph because it is _ in water. If it cannot dissolve, the ions of the _ are unable to move. If no charged particles can move, a substance will _ conduct electricity. Covalent Bonding: Covalent compounds are made up of _. A molecule is formed from non-metal atoms held together by strong covalent _. Covalent bonds are formed due to the _ of a pair of electrons between adjacent atoms. 21

22 Non-metal atoms have almost outer energy levels. To be completely, non-metal atoms must gain electrons to fill their outer energy levels. When covalent molecules are formed, rather than take electrons from other atoms, adjacent atoms _ electrons. 1 covalent bond represents _ shared pair of electrons. e.g. bonding in a molecule of hydrogen bonding in a molecule of water bonding in a molecule of nitrogen chloride 22

23 Summary: For a substance to conduct electricity, chargedd particles must be able to and carry the electrical charge. If we increasee the of charged particles we will increase the quantity of electricityy the substance can transmit. A covalent bond is a pair off electrons between two adjacent t non-metal atoms. Lesson 9: Ions on the Move Electrolysis: Metal elements form at the electrode. Positive _ ionss are attracted too the negative electrode. At the negative electrode the positive metal ions electrons and are transformed into metal atoms. At the negative electrode, metal ions are a _. 23

24 Non-metal elements form at the _ electrode. _ Negative non-metal _ electrode. _ are attracted to the positive When carrying out an must be used. At the positive electrode the negative non-metal ions electrons andd are transformed into non-metal atoms. At the positive electrode, non-metal ions are. electrolysis, a _. _. powerr supply This gives a _ positive electrode and a fixed negative electrode. By using this we can clearly identify the _ of the electrolysis. Covalent solutions do not contain _ particles they cannot conduct electricity. Covalent solutions cannot be. Electrolysiss of Zinc Iodidee Solution: 24

25 Extracting Metals: metals such as aluminium, sodium and potassium are extracted from their ores using electrolysis. Compounds containing the metal desired are dissolved in a suitable _ before being electrolysed. The metal is always obtained from the electrode of the electrolysis apparatus. Summary: Positive _ ions are attracted to the negative electrode during an electrolysis. At the negative electrode, metal ions electrons to form metal atoms. Metal ions are _. Negative non-metal ions are attracted to the electrode during an electrolysis. At the positive electrode, non-metal ions electrons to form non-metal atoms. Non-metal ions are. Lesson 10: What makes an acid or alkali? When sodium is burnt in a plentiful supply of air, sodium _ is produced. 25

26 When calcium is burnt in a plentiful supply of air, calcium _ is produced. These are both metal. To test the effect a metal oxide has on we need to dissolve the metal oxide in water to make a solution. We can only test an _ solution s ph. metal oxide formula soluble? acid, alkali or neutral? calcium oxide magnesium oxide aluminium oxide Soluble metal oxides dissolve to produce an solution. Insoluble metal oxides have effect on the of water. When carbon is burnt in a plentiful supply of air, carbon _ is produced. When nitrogen is sparked in a _ engine, this sparking causes nitrogen to combine with oxygen to form nitrogen dioxide. 26

27 To test the effect a non-metal oxide has on ph we need to dissolve the non-metal oxide in _ to make a solution. We can only test a aqueous solution s. When sulphur is burnt in a plentiful supply of air, sulphur _ is produced. When sulphur dioxide dissolves in water, sulphurous acid is produced. A solution of sulphurous acid will cause universal indicator to change colour from _ to red. When carbon dioxide dissolves in water, carbonic acid is produced. A solution of carbonic acid will cause universal indicator to change colour from green to _. Coal naturally contains sulphur compounds. When coal is burnt sulphur _ is released. This dissolves in water water vapour in the clouds to produce an solution. The acidic solution falls as acid. To combat acid rain, some countries at sodium oxide to lakes. This dissolves in the water to produce an solution. The alkali neutralises the acid in the lakes. Summary: Soluble metal oxides dissolve in water to form an solution. 27

28 Insoluble metal oxides have no effect on the of water. Soluble non-metal oxides dissolve in water to form an solution. Lesson 11: Acid Formulae Acids are compounds whose chemical names suggest that they are salts of. sulphuric acid is hydrogen. phosphoric acid is hydrogen _. nitric acid is hydrogen _. hydrochloric acid is hydrogen. Using valency rules work out the formulae for all of the above acids. 28

29 The acid solution conducts _, therefore acids must dissolve in waterr to release. name formulaa positive ion negative ion sulphuric acid nitric acid phosphoric acid hydrochloric acid 1 litre of 1M sulphuric c acid contains _ as many hydrogen ions as 1 litre of 1M hydrochloric acid. We know this from the formulae for each acid: Hydrochloric Acid (HCl) _H + :_Cl - 29

30 Summary: Sulphuric Acid (H 2 SO 4 ) _H + :_SO 4 2- Acids are substances. molecules when present as pure When dissolved in water, the covalent molecules split apart to release. Each acidic solution contains _ ions. Acidicc solutions conduct. Lesson 12: Breaking Acids Electrolysis can be used to break an compound into its constituent elementss using electricity. The ionic compound must be present ass a liquid or dissolved in solution The ions that make upp the ionic compound mustt be to move. 30

31 Positively charged ionss are attracted to t the negative electrode. Here they electrons s to formm atoms. (A _ reaction.) Negatively charged ions are attracted to the positive electrode. Here they electrons s to formm atoms. (An _ reaction.) Summary: If an acidic solution iss electrolysed, gas is released at the negative electrode. At the negative electrode positive hydrogen ions electrons to form hydrogen atoms. The hydrogen ions aree oxidisedd ( electrons). 31