chemistry&MODULE FIVEIONIC BONDINGWhen metals react with non-CHEMICALS IN THE ATMOSPHEREmetals, electrons are transferredfrom the metal to the non-metal, creating an ion.The earth is surrounded by an atmosphere made up ofThe resulting compound is an ionic compound. Themany different substances, some of which are elementsmetal and non-metal are charged [+] and [-] respectively.and some of which are compounds too.217isThere is a strongOTHERAir contains a number(whingelectrostatic force ofof different gases, with25,attraction between thecertain concentrations oftwo oppositely chargedthese varying fromions called an ionicplace to place and so are781bond.MITROSENmagnesium ionoxids canusually given for dry air.Ionic compounds arranged in a lattice form crystals,MOLECULAR COMPOUNDSlike in sodium chloride (NaCLz). Because of thestrong bond, lots of energy is needed to break them,Most non-metal elements are molecular, and most ofand so ionic compounds have high MPs and BPs.them are diatomic, meaning they go around in pairs.They do not, however, conduct electricityExamples of these are N2, C22 O2 and Br2 Most compoundsbecause the lons are firmly held in place,between 1-metals are also molecular, e.g. H2O, CO2 and NH3.All of these substances have very strong covalent bondswhich means they cannot move to conduct anbetween the atoms, but much weaker Forces holdingelectrical current. As a liquid they are freethe molecules together It is these 'intermolecular bondsto move, and therefore do conduct electricitythat break when boiled or heated, not the covalent ones.Diamond and Graphite are good examples ofAnd because the weak intermolecular bonds break sohow covalent bonds differ within compounds.easily, they have law melting points $ boiling points.Diamond has strong covalentcorapoundformulacovalent or ionicMP/'CBP/'CGraphite, bonds throughout, which has unlike stronghydrogenchionideHCLcovelent-115-85bonds between atoms butmethonsCH.coralentnot between layers, and as-182-164diamondgraphitsa result it flates easily.sodiumBallionic1.0741,686CalciumoxideCoOionic2,2843,123THE LITHOSPHEREAll solid matterRANTLEThe easiest way to represent covalent bonds is touse either a 2D or a 3D molecular diagram.on Earth is partOUTER CORTof something calledCOVALENT BONDING - HIGHERthe lithosphere,INNER LOKEcomposed of the crestCRUSTcovalent bonding is when two non-metal atoms shareand the manHe.a pair of electrons in the outer electron-Shell in orderto completely fill it (usually with eight electrons)ELECTROLYSIS - STEP BY STEPMost importantly, covalent bonds are very strong.1 Break up the structure,The strong bond between atons(anode)(callnose)either through heating-or dissolvingas a result of this is called2. Place the electrodes inelectrostatic attraction betweenthe solution they willHClthe posative nuclei and thepull the ions apart.negative electrons. sometimes- In the example ofan atom is part of multiple bondscopper chicride, all thepositive metal ions (thelike carbon dioxide, in whichcopper) go to the cathode $hydrogen chloride (HCL)one carbon atom is covalentythe negative ions (chlorine)go to the anode.bonded to two oxygen atoms.