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Chains and rings. Basic concepts. You need notes on; Explain each type of formula and give examples for each using hexane and pentene (for molecular, general, structural, displayed, skeletal, 3-D, empirical) Know the stem name for chains with 1-10 and 20 carbons. Chains and rings.
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Chains and rings Basic concepts You need notes on; Explain each type of formula and give examples for each using hexane and pentene (for molecular, general, structural, displayed, skeletal, 3-D, empirical) Know the stem name for chains with 1-10 and 20 carbons.
Chains and rings Types of functional groups Alkanes Alkenes Arenes Alcohols Halogenoalkanes Carboxylic acids Esters Aldehydes Ketones Amines
Types of formula Many different types of formula are used within chains and rings dependent on what you are trying to show. Each has its own use and you must be able to write any compound in any of the formats stated. For the purpose of showing each formula we will be looking at the alkane propane, C3H8.
Displayed formula Types of formula This shows the number of each atom in the molecule. It can be found from empirical formula and molecular mass. Molecular formula C3H8 This shows a ratio of the elements within the compound for a homologous series General formula CnH2n+2 This shows every atom and every bond in the molecule; - is single bond; = a double
3-dimensional Types of formula This is a shorthand form of the displayed formula. Written without showing the bonds Structural formula CH3CH2CH3 This shows only the carbon skeleton as straight lines, each of which represents C-C bond, plus any functional groups. Skeletal formula This gives the best representation of the shape of a molecule Empirical C3H8 Simplest ratio of the atoms
3) Displayed 6) 3-Dimensional Types of formula Do the same now for the ALKENE, propene 1) Molecular C3H6 2) General CnH2n 4) Structural CH2CHCH3 5) Skeletal 7) Empirical CH2
Types of formula You must also be able to name various length carbon chains, the following needs to be learnt. 1 carbon = meth 7 carbons = hep 2 carbons = eth 8 carbons = oct 3 carbons = prop 9 carbons = non 4 carbons = but 10 carbons = dec 5 carbons = pent 20 carbons = eicos 6 carbons = hex