introduction into organic chemistry 6A Flashcards
when naming organic substances what must you remember?
the longest continuous chain i the stem
any side-chains or less important functional groups are added as prefixes at the start of the name. they should be in alphabetical order
what does a mechanism do?
it breaks down a reaction into individual stages. they are diagrams that use curly arrows to show how electron pairs mar around when bonds are broken.
what do curly arrows show in a mechanism?
they show how the electron pairs move around. they show where they go during a reaction. the arrow starts where the bond or lone pair is at the beginning of the reaction and then points to where the new bond is formed at the end of the reaction or the atom where the electrons go to.
what are the different types of mechanism?
radical substitution on halogens in alkanes to form halogen alkanes
electrophilic addition pf halogens and hydrogen hydrides to alkenes to form halogenoalkanes
nucleophilic substitution of primary halogenoalkanes with aqueous potassium hydroxide to make alcohol and with ammonia to make amines
how will classifying reagents help to predict what reaction will happen? -nucleophiles
Nucleophiles are electron pair donors. they are often negatively charged ions nor species that contain a lone pair of electrons. they are electron rich and so are attracted to places that are electron poor so they like t react with positive ions - atoms with polar bonds are often attacked by nucleophiles
how will classifying reagents help to predict what reaction will happen? -electrophiles
electrophiles are electron pair acceptors. they are often positively charged ions. they are electron poor and so they are attracted to places that are electron rich. they like to react with negative ions, atoms with lone pairs and the electron rich area around a C=C bond
how will classifying reagents help to predict what reaction will happen? -radicals
radicals have an unpaired electron e.g. the chlorine atom produced when UV light splits a Cl2 molecule. because they have impaired electrons they are very, very reactive, they will react with anything positive, negative or neutral
why are the two types of isomerism
stereoisomerism and structural isomerism
what is a structural isomer?
in structural isomers the atoms are connected in different ways so although the molecular formula is the same, the structural formula is different
what are the three different types of structural isomer?
chain isomer, positional isomer and functional group isomer
what is a chain isomer?
the carbon skeleton can be arranged differently - these isomers have similar chemical properties but their physical properties, like boiling point, will be different due to the change in shape of the molecule
what is positional isomerism?
the skeleton and the functional group could be the same, only with the functional group attached to a different carbon atom, these also have different physical properties and the chemical properties may also be different.
what is a functional group isomer?
the same atoms can be arranged into different functional groups. they have very different physical and chemical properties
