Structure and Bonding - Metallic Bonding Mind Map

Structure and Bonding - Metallic Bondingmetallic structurePhysical metal propertiesAlloyssubtances with metallic structure:pure metalsaluminiumcopperpotassiumsodiumAlloys - mixtures of metalssteelbrassstructure of a metalpositive metals ions surrounded by a 'sea of mobile delocalised electrons'metallic bonding - strong electrostatic attractionbetween positive metal ions and the 'sea of delocalised electronsarrangementclose together in a regular mannerknown as metal latticeattraction between the delocalised electronsand the metal cations is responsible for the strength of the metal latticedelocalised valnece electrons move freely like a cloud of negative chargemetals have high densitymajority of metals have higher densities than non-metalsgroup 1 metals, also known aslight metals happen to be exceptionsto this generelizationthis is because of the tightly packed crystallattice of the metallic structurestrength of metallic bonds for different metalsreaches a maximum around the centre of thetransition metal series as those elements have large amiunts od delocalised electrons in the metallic bondsmetals have high melting and boiling pointsmetal atoms are held together by strong metallic bondsa lot of energy is required to overcomethese bondsexplains the high melting and boiling pointsmetals are good electrical conductorswhen a potential difference is applied across theends of a metallic conductor, delocalised electrons will be attracted and hencemove towards the positive endmovement of charge known as electric currentmetals are good conductors of electricity because theyhave delocalised mobile electrons that move towards thepositive terminal when connected to a circuitmetals are good heat conductorsmetal atoms are closely packedheat can be transferred from one atom to the next byvibration as they are close togetherthe free electrons also suddenlyacquire more energythey move faster and collide with the otherelectrons, transferring part of the energythus heat is easily conducted from oneend to the other end of the metalMetals are malleable and ductilemalleable (can be rolled into sheets)when a metal is bentlayers of cations in the metal lattice slideover one another easily and fit into new positionsthe shape of the metal has changedbut it does not break apartductile (can be pulled into wires)when force is applied to1 layer of cationsthis layer easily slides over the other layersmakes the metal longer and flatter without breaking apartthis is possible because metallicbonding reamin largely undisruptedmetal cations are shielded from each other's repulsions by the 'sea of delocalised electrons' in between themshielding is present no matter how much the lattice is distortedbending and shearing forces can deformmetal lattices without shattering thema homogenous mixture of a metal andanother elementstronger and harder than pure metalsa metal can be made stronger and harder by the addingother elements into its structureThe presence of atoms of a different size disrupts theregular arrangement of the metal atoms prevents themetal atoms from sliding over one another easily
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