Introduction to Organic Chemistry Flashcards
what is a functional group?
The atom or group of atoms that is responsible for most of the chemical reactions of a molecule
what is a homologous series?
a family of compounds with the same general formula and similar chemical properties. In a series, each member differs by the addition of a CH2 group and there is a gradual change in physical properties
what is a homologous series?
a family of compounds with the same general formula and similar chemical properties. In a series, each member differs by the addition of a CH2 group and there is a gradual change in physical properties
what is a hydrocarbon
molecules containing hydrogen snd carbon atoms only
what does saturated mean
molecules containing no double bonds
what are stereoisomers?
molecules with the same molecular and structural formula but a different spatial arrangement of atoms
what are structural isomers?
molecules with the same molecular formula but different isomers
what are chain isomers?
Type of structural isomerism: structural isomers that differ having a different carbon chain
What are position isomers?
Type of structural isomerism:structural isomers that differ by having the functional group in a different position
What are functional group isomers?
Type of structural isomerism: structural isomers that differ by having a different functional group
what is a molecular formula?
Formula that gives the actual number of atoms of each element in one molecule e.g. C4H10
What is an empirical formula?
Formula that gives the simplest ratio of atoms of each element in a compound e.g. C2H5
What is a general formula?
This shows the number of atoms of each element in a substance which has n carbon atoms. All the molecules in a homologous series have the same general formula
What is a structural formula?
This shows how the atoms are joined together in a molecule
What is a displayed formula?
This shows all the bonds and atoms in a molecule
What is a displayed formula?
This shows all the bonds and atoms in a molecule
What is a skeletal formula?
This uses lines to represent bonds. Each point represents a C atom. H atoms and bonds to H atoms are not usually shown(unless part of a functional group e.g alcohol, aldehyde). Other atoms (e.g. O, N, F, Cl, Br, I, S) are shown.
Give an example of a chain isomer of butane
methylpropane
Give an example of a chain isomer of butane
methylpropane
What is the structural formula of butane?
CH3CH2CH2CH3
In a structural formula, how is a side chain shown?
In brackets
What is the structural formula of methylpropane?
CH3CH(CH3)CH2CH3
How is a side chain named?
by adding -yl to the normal alkane stem
If there are more than 1 of the same alkyl side chain or functional group, how do we name them?
di- for 2
tri- for 3
tetra- for 4
we add these prefixes in front of the alkyl side chain or functional group name
Name all the chain isomers of hexane
-hexane
-2-methylpentane
-3-methylpentane
-2,3-dimethylbutane
-2,2-dimethylbutane
If there is more than one alkyl side chain, how are they listed?
in alphabetical order
Give an example of functional groups
alkenes
halogenalkane
alcohols
aldehyde
ketone
carboxylic acid
ester
amine
nitrile
What is the nomenclature of an alkene?
-ene
What is the nomenclature of an halogenalkane?
chloro-
fluoro-
iodo-
bromo-
What is the nomenclature of an alcohol?
-ol
What is the nomenclature of an aldehyde?
-al
What is the nomenclature of a ketone?
-one
What is the nomenclature of a carboxylic acid ?
-oic acid
What is the nomenclature of an ester?
alkyl -oate
What is the nomenclature of an ester?
alkyl -oate
What is the nomenclature of an amine?
alkyl -amine
What is the nomenclature of a nitrile?
-nitrile
What is CH3CH2CH(CH3)CH2CHFCH3 ?
2 flouro, 4 methyl hexane
Give an example of an alkene
ethene
Give an example of a halogenalkane
chloroethane
Give an example of a halogenalkene
chloroethane
Give an example of an alcohol
ethanol
Give an example of an aldehyde
ethanal
Give an example of a ketone
propanone
Give an example of a carboxylic acid
ethanoic acid
Give an example of an ester
propyl ethanoate
Give an example of an ester
propyl ethanoate
Give an example of an amine
ethylamine
Give an example of a nitrile
ethane nitrile
write out the formula for 2 fluoro 4 methyl hexane
CH3CHFCH2CH(CH3)CH2CH3
which compounds are chain isomers of 1 chlorobutane
1 chlorobutane
2 chlorobutane
1 chloro methylpropane
what is primary, secondary and tertiary halogenalkane?
primary halogenalkane: carbon joined to halogen is only attached to one other alkyl group
secondary halogenalkane: carbon joined to halogen is only attached to two other alkyl groups
tertiary halogenalkane: carbon joined to halogen is only attached to three other alkyl groups
What are alkenes?
Unsaturated hydrocarbons with at least one carbon-to-carbon double bond
How do alkenes compare with alkanes?
Alkenes are more reactive than alkanes due to the double bond. Alkenes have lower boiling points than alkanes, but the boiling point increases as the size of the molecule increase.
Draw the skeletal formula of pent-1-ene
Draw the skeletal formula of pent-1-ene
Give an example of functional group isomerism and draw the structure
hexene can be drawn as a cycloalkene:
Using C4H8 as an example give 1 isomer for each form of isomerism.
position isomer: but-2-ene
chain isomer: methylpropene
functional group isomer: cyclobutane
What is stereoisomerism?
Molecules with the same molecular and structural formulas but a different arrangement of the atoms in space.
What are the 2 types of stereoismerism?
-E-Z isomerism
-optical isomerism
What is E-Z isomerism?
caused by molecules with a C=C with two different groups attached to each C of the C=C
What is optical isomerism?
Caused by C with atoms having four different grips attached leading to molecules that are non superimposable mirror images of each other
How does E-Z isomerism occur?
E-Z isomerism is a type of stereoisomerism that occurs when there is restricted rotation around a double bond in a molecule.
What are E isomers?
The highest priority groups for each carbon are on opposite sides of the molecule
What are Z isomers?
The highest priority groups for each carbon are on the same sides of the molecule
How can you determine which group has the highest priority?
you can look at the atom directly attached to a carbon atom and give higher priority to the atom with the higher atomic number.
What kind of isomerism does 2 fluoro, 3 bromo butene have?
z isomerism
What kind of isomerism does 2 fluoro, 3 bromo butene have?
z isomerism
What kind of isomerism does 2 fluoro, 3 bromo butene have?
z isomerism
Does CH3CH=CHCH3 show stereoisomersim?
yes
Does CH3CH=C(CH3)2 show stereoisomerism?
no
Does CHBr=CHBr show stereoisomerism?
yes
Does CHCl=CH2 show stereoisomerism?
no
Draw the E-Z isomers of 1-chloropropene
Draw the E-Z isomers of 3-methypent-2-ene
Deduce the empirical and molecular formula of..
mf: C6H12O2
ef: C3H6O
What is an empirical formula?
Empirical formula is the simplest whole number ratio of the elements present in one molecule or formula unit of the compound
How do we calculate the empirical formula?
Write out the mass or percentage of each element
Divide each mass or percentage by the Ar of the element (not the Mr)
Find the simplest whole number ratio of these numbers by dividing by the smallest number.If the values come out as near ½’s then times them by 2, if they are near 1/3’s then times by 3
Determine the empirical formula of a compound that contains 85.7% carbon and 14.3% hydrogen.
What is a molecular formula?
The molecular formula gives the exact numbers of atoms of each element present in the formula of the compound
How can we find out the molecular formula?
The molecular formula can be found by dividing the relative formula mass of the molecular formula by the relative formula mass of the empirical formula. Multiply the number of each element present in the empirical formula by this number to find the molecular formula
The empirical formula of X is C4H10S1 and the relative formula mass of X is 180. What is the molecular formula of X? Relative Formula Mass: carbon-12 hydrogen-1 sulfur-32
Mr=90
180/90=2
C8H20S2
Compound X, which contains carbon, hydrogen and oxygen only, has 38.7% carbon and 9.68% hydrogen by mass. Calculate the empirical formula of X.
CH30
When you make a new substance by a chemical reaction, you may not get all the expected amount of product. What are the three reasons as to why?
-the reaction may be reversible
-some of the product may be lost when it is separated from the reaction mixture
-some of the reactants may react in other reactions
How is percentage yield calculated?
percentage yield=actual yield/theoretical yield x100
How is percentage yield calculated?
percentage yield=actual yield/theoretical yield x100
A student heats a reaction mixture containing 6.50 g of propan-2-0l with an exces of oxidsing agent.
The propanoic acid separated from the reaction mixture has a mass of 3.25 g
СН3CH2CH2OH → CH3CH2COOH
Work out the percentage yield
40.5%
A student heats a reaction mixture containing 6.50 g of propan-2-0l with an exces of oxidsing agent.
The propanoic acid separated from the reaction mixture has a mass of 3.25 g
СН3CH2CH2OH → CH3CH2COOH
Work out the percentage yield
40.5%
What is atom economy?
Atom economy studies the amount of reactants that get turned into useful products. It illustrates what percentage of the mass of reactants become useful products.
How do we calculate atom economy?
atom economy= total Mr of the product/total Mr of all reactants x100
Hydrogen can be manufactured by reacting methane with steam: CH4+H20->3H2+CO
Calculate the atom economy for the reaction.
17.6%
