Chemistry Bonding, Structure & Properties of Matterch

chemical bonds

Compounds between 2 or more elements. There are 3 types of strong chemical bonds: ionic, covalent and metalic

ionic bonding

chemical bond between a metal and a non-metal. The metal looses an electron and becomes a positively charged ion and the non-metal gains an electron and becomes a negatively charged ion. the elements involved are the metals in groups 1 and 2, and the non-metals in group 6 and 7.

ions

element that has either gained or lost an electron

ionic compounds

giant ion structure held together by oppositley charged ions strong electrostatic attraction. e.g. Na+ and Cl-. high melting and boiling point. when melted or disolved in water they can conduct electricity bc the ions are free to move around. when solid it cant conduct electricity bc the ions are fixed in place

covalent bonding

non-metal atoms bonded by one or more pairs of electrons. smaller compounds with covalent bonds have stronger forces between eachother.

polymers

structure formed by atoms that are covalentley bonded, solid at room temperature, relitavley high melting and boiling points

giant covalent structures

large amount of atoms with covalent bonds in a lattice structure. e.g. diamond or silicon dioxide. very high boiling and melting point bc all the atoms have strong covalent bonds

metalic bonding

two metals. consists of positive ion and a system of delocalised electrons, the electron system are electrons lost by other atoms to form a positive ion. the delocalised electrons are free to move and are shared throughout the structure so the bonds are strong

strong electrostatic force between the electrons and the positve ions

three states of matter

solid liquid gas, melting point, freezing point and condensing point

particle theory

energy need to change states depends on the force between particles. the stronger the forces between the substances the higher the melting point and boling point.

limitations to simple model of representations bc no force is applied and the shapes are all spheres

state symbols

solid (s), liquid (l), gas (g) and aqueous (aq)

properties of small molecules

liquid and gas, low intermolecular forces which means they have low boiling and melting point (exept covalent bonds). they do not conduct electricity because they do not have overall electric charge

properties of metals

atoms with metalic bonds. most metals have high boiling and melting points. the layers of atoms can slide over eachother allowing the metal to bend

properties of alloys

2 or more different metals, this means there are different sizes of atom layers which makes it harder for the alloy to be bent, this means alloys are harder than pure metals

metals as conductors

delocalised electrons carry electrical charge. they also transfer thermal energy

diamond

each carbon atom is bonded to another 4 carbon atoms. diamonds is very hard and has very high boiling and melting points and it does not conduct electricity. covalent bond

graphite

carbon covalentley bonded to 3 other carbon atoms. forms hexagonal rings as layers but the layers are not covalentley bonded, this means that they can slide over eachother making carbon soft and slippery. each carbon atom has 1 delocalised electron allowing it to conduct electricity

graphene

single layer of grahite, graphene is strong because the atoms are titley bonded togther, it is also flexible because the planes of atoms can bend relitivley easily. this makes it useful in electronics and composites

fullerene

different number of hollow shaped carbon atoms. hexagonal shaped but it can also contain 5 or 7 carbon atoms. first fullerene to be dicovered is C60 with a spherical shape

carbon nanotubes are cylindrical fullerenes with high length to diameter ration. can be used as lubricant or in tennis rackets