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A salt= a compound entirely of ions • Gas: Matter has no fixed volume or shape. It will adopt the volume and shaper of its container. • Liquid: Matter has a distinct volume, but no specific shape. • Solid: Matter has a distinct volume and a distinct shape. • The state matter adopts depends on the surrounding temperature and pressure. Classifying matter (Properties of matter) • Look at it – state, size, shape, colour. • Measure its mass. • Measure its volume. • Smell it – never do this in a chemistry lab. • Taste it – never EVER do this in a chemistry lab. • We can also describe: • Ductility (how well it stretches) • Malleability (how well it deforms) • Lustre (how shiny it is). • Better yet, we can measure: • Hardness (the Mohs scale). • Boiling point (ºC, K). • Melting point (ºC, K). • Solubility (mass per unit volume). • Thermal conductivity (W m-1 K-1) • Electrical conductivity (A2 s3 m-3 kg-1) Elements are pure substances – all atoms of a chemical element are indistinguishable from each other Compounds are pure substances that consist of two or more chemical elements combined chemically in definite proportions. • A mixture is a non-chemical combination of two or more pure gas, liquid or solid substances. • Mixtures can be solid, liquid or gas, and can consist of multiple phases. • A solution is a homogeneous mixture. • Any part of a solution is indistinguishable from all other parts. • Solutions can be solid, liquid or gas, but consist of only a single phase. Daltons Atomic Theory • Matter consists of tiny particles called atoms. • Atoms are indestructible. In chemical reactions, the atoms rearrange, but they are not created or destroyed. • In any sample of a pure element, all atoms are identical in mass and other properties. • The atoms of different elements differ in mass and other properties. • When atoms of different elements combine to form a given compound, the constituent atoms in the compound are always present in the same fixed numerical ratio. • •

Atomic Number (below) – the number of protons in the atomic nucleus, unique for every element. • The Mass Number (Above) – the number of protons plus the number of neutrons in the atomic nucleus. Isotopes= different number of neutrons 1. Naming ionic compounds Look up elemental symbols, or polyatomic ion formula. 2. Look up ion charges. 3. Swap the cation & anion charges to give the cation/anion formula subscripts. This balances charge. Naming Molecular Compounds 1. The element left-most on the periodic table appears in the formula first. If both elements are in the same group, the bottom-most element appears first. 2. The first element in the formula retains its elemental name. 3. The second element in the formula begins with a root derived from its elemental name and ends with the suffix “-ide”. 4. When there is more than one atom of a given element in the formula, the name of the element is usually prefixed according to that number. mass( g) −1 m M olar mass=M = = ( g mol ) n amount (mol) amount (mol ) n = (mol L−1 ) concentration ¿ c= V volume(L) •

Enthalpy: • Related to the internal energy of matter. • Entropy: • A measure of disorder in matter. • Gravitational energy – due to interaction between massive objects. • Electrostatic energy – due to interaction between electrostatic +/- charges. • Thermal energy – due to motion of atoms, molecules. • Radiant energy – due to light and electromagnetic radiation. • Magnetic energy due to interaction between magnetic objects. • Each of these examples is either a form of kinetic or potential energies. • Open Systems: Matter and energy can be transferred. • Closed Systems: Energy can be transferred, matter cannot. Isolated Systems: Neither matter nor energy can be transferred • A change in DU corresponds to either the system producing energy, or consuming energy. This is observed as: • Heat (q): The temperature of the system increases or decreases. Note – heat, like energy, cannot be measured. Only the temperature change that results from the flow of heat can be observed. • Work (w): The system causes the motion of an object with mass to move some distance against some force. q (J ) Specific Heat Capacity= C= m ( g) × ΔT (K ) where q = quantity of heat transferred by heating or cooling. •

m = mass of substance present. DT = change in temperature (i.e. Tfinal – Tinitial) • Pascals – 1 Pa = 1 N/m2 • Bar – 1 bar = 105 Pa = 100 kPa • mm Hg or Torr – The difference in the heights in mm (h) of two connected columns of mercury • Atmospheric pressure – 1.00 atm = 760 Torr (760 mm Hg) V1 V2 V3 PV P V P V P 1 V 1 = P 2 V 2 = P 3 V 3 . . . . T 1 = T 2 = T 3 . . . 1T 1 1 = 2T 2 2 = 3T 3 3 . . . Ideal Gas Law

V µ

nT ænT ö or V =R ç ÷ P è P ø

D e n s it y (d ) =

M a s s (m ) V o lu m e ( V )

M o le s ( n ) =

M a s s (m ) M o la r M a s s ( M )

n P m P m M P = Þ = Þ d = = V RT M V RT V RT e f f u s io n r a t e (g a s 1 ) m o la r m a s s ( g a s 2 ) = e f f u s io n r a t e (g a s 2 ) m o la r m a s s ( g a s 1 ) W a v e le n g t h ( m ) ´ F r e q u e n c y (s - 1 ) = V e lo c it y ( m / s )

l ´n = c l =

h m v

E =h n

and

c n = l

ß hc E = l

Rhc En = - 2 n

Lewis structures how many electrons in full shell? Leads to how many bonds can be made (possible-current) Formal charge=#of valence electrons in neutral unbonded atom – (unshared electrons + Shared electrons(lines =2 but half it!, therefore line =1 for equation)) Put in all electrons then work out how many are leftover and put them in. Formal charge for each atom and overall (Cx7=28+Ox1=6 =34) Cyclo/alkanes are hydrocarbons (only C and H) general formula = CnH22n+1 Valence Electron Pair Repulsion Theory VSPER-electrons in all 4 bonds around the carbon will repel each other and try to be as far away from each other as possible. Line structure- each point and end=C so straight line =2C Isomers are chemical compounds that have the same molecular formula. Constitutional (or structural) isomers are isomers which have different structural formulae Butane CH3CH2CH2CH3 Isobutane CH3CH(CH3)2 1. Alkane names all end in -ane. 2. Find the longest carbon chain i.e. 8 carbons 3. Find the position (number) and name of any substituent chains (#at begin) (second lect for pics) 4. Number the chain so that the first substituent number is the lowest possible Cycloalkanes Are saturated hydrocarbons that contain carbon atoms joined to form a ring; the carbon atoms are still sp3 hybridised Newman projections (Clock) eclipsed is in line, staggered is half between 1. Torsional Strain 2. Angle Strain 3. Steric Strain Cis-Trans Isomers vs Optical isomers (Optical is the same when put ontop of eachother) Cis=same side of plane-mirror. Trans= non of the other two. Combustion - general equation for an alkane Halogenation of Alkanes

Alkenes are unsaturated Hydrocarbons - CH compounds that contain one or more double carbon to carbon bond. CnH2n 1. the ‘ane’ ending is replaced by ‘ene’. 2. If there is more than one double bond then it is -diene, -triene, - tetraene, etc. 3. the base name for the alkene is determined by finding the longest carbon chain that includes as many of the double bonds as possible. 4. the carbon chain is numbered so that the first double bond encountered has the lowest possible locant number. (middle number between dashes) 5. the position of each double bond is indicated by the lowest numbered carbon in the double bond....