TOPIC 6 - ORGANIC CHEM

• Measure the boiling temp . More purity = closer to databook bp value. • Any impurities will raise the boiling temperature To determine bp: -substance heated above its bp, allowed to cool down and drawn into capillary tube and temp change.

• Add the chosen solvent to form 2 layers in a separating funnel (2 seperate liq with 2 diff densities) • Add stopper and gently shake • Allow the contents to settle into two layers • Remove the stopper and allow the lower layer to drain into a flask and the upper into a different flask

• Anhydrous calcium chloride to remove water and absorb moisture. • The drying agent (does not react with organic liq) can be removed by: • Filtration • Decanting

• separate liqs with very diff bp • easier to set up and quicker • only used if 25’C difference in bp 1. liq heated, liqs with low bp evaporates/boils off first and passes into condenser and collected in reciever seperately. Other liqs have higher bp evaporate off later. if temp begins to rise indicates diff compound boiling.

used to seperate liq. with similar bp - filled with glass beads/broken acts as an surface area which vapour leaving the column can condense. • Crude oil is heated in a furnace which turns most of it into vapour • Near the top is where the shorter chain molecules condense • Near the bottom is where longer molecules are as they have a higher melting point • Different columns have different temperatures where different length carbon chains condense

A compound that contains hydrogen and carbon only

Contain single bonds only. Hydrocarbons with the maximum amount of hydrogens possible

Contain 1 or more double bonds. Hydrocarbons without the maximum amount of hydrogens possible

The simplest whole number ratio of atoms in a compound

The actual number of atoms in each molecule

Shows the arrangement of atoms carbon by carbon with the attached hydrogens and functional groups

Shows the bonds of the carbon skeleton only, with any functional groups

Shows how all the atoms are arranged, and the bonds between them, drawn out

The group of atoms which gives an organic compound its characteristic properties and reactions

A series of compounds with the same functional group and general formula and similar chemical properties, which differ by CH2 from the next member

alkenes - CnH2n alkanes - CnH2n+2 Haloalkane - CnH2n+1X Alcohols - CnH2n+1OH Aldehyde - CnH2n+1CHO Carboxylic acids - CnH2n+1COOH Ketone - CnH2nO carbonyl bond not at end of C chain when naming it has to be alphabetical and always count and write position of C in one direction.

Joining two or more molecules together to form a larger molecule

Joining together lots of simple molecules, same REPEATING UNITS - MONOMERS to form a large molecule - POLYMER.

occur in alkenes Because the presence of C=C leads to restricted rotation, whereas in alkanes the atoms can rotate freely, without restriction. due to overlap of p-orbitals = pi bond. - TRIGONAL PLANAR 120’ - due to 3 areas of electron densities repel each other E = TRANS Z = CIZ - atoms/groups on each side with higher priority with higher Mr/Ar to determine E-Z isomerism • Ethene do not exhibit e/z as atoms are same on either side

mainly made up of Alkanes. energy comes from burning fossil fuels, crude oil and natural gases. - Fractional distillation takes place: as chain length increases bp increases, volatility and viscosity, flammability and reactivity decreases.

• Cracking • Reforming • Fractional distillation

The breakdown of longer chain molecules into smaller ones by heating with a catalyst. Because the demand for longer chain hydrocarbons is much less than the demand for shorter chain hydrocarbons, therefore cracking is used to turn longer chain into shorter chain hydrocarbons • THERMALYTIC CRACKING - produces higher prop of alkanes and alkenes - 7000kPa - high temp 1200K • CATALYTIC CRACKING : - produces aromatic compounds/cyclic rings and H2 gas - low temps and normal press - zeolite catalyst

conversion of straight chains alkanes/hydrocarbons into branched chain and cyclic hydrocarbons as they burn less efficiently when heated - so heated with a catalyst Pt helps it burn more smoothly in engine pentane = cyclopentane + H2 heptane = methylbenzene + 4H2

separate liq into fractions b boiling and condensing with similar bp near bottom, fractions with large moleculs and longer chains with high bp near top fractions with smaller molecules with low bp - rise higher up column and collected at the top. they condense and collect bottom fraction column = RPKDFB down the column fractions - incr in bp and decr in voltality and viscosity