Introduction to organic chemistry Flashcards
Define hydrocarbons.
Hydrocarbons are compounds that are made up of carbon and hydrogen only.
Define functional group.
A functional group is an atom or a group of atoms in an organic molecule which determines the characteristic chemical reactions. Organic molecules are classified by the dominant functional group.
Define homologus series.
Homologus series is a group of organic compounds having the same functional group, the same general formula and similar chemical properties.
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What is a general formula?
The general formula is the formula that represents a homologus series of compounds using letters and numbers. For example the general formula of alkanes are CnH2n+2
What is the general formula for alkenes?
CnH2n
What is the general formula of halogenoalkanes?
CnH2n+1X
where x=f,Cl,Br,I
How do we name halogenoalkanes?
The prefixes fluoro,Chloro,Bromo and Iodo are used. For example Chloropropane.
What is the general formula for alcohol?
CnH2n+1OH
How do we name organic molecules with alcohol functional group?
Alcohol is named by identifying the longest straight carbon chain containing the -OH group. The -ane suffix is replaced with -anol and the location of the -OH group on the chain is designed by a number. For example propan-1-ol.
What is the general formula for aldehydes?
CnH2n+1CHO
How do we name aldehydes?
Aldehydes take their name from their parent alkane chains. The -e is removed from the end and is replaced with -al. For example propanal. Aldehyde is always at carbon 1. Aldehyde has greater priority over hydroxyl and amino group and ketones. Carboxylic acid has more priority over aldehydes.
What is the chemical formula for ketones?
CnH2n+1COCmH2m+1
How do we name ketones?
The name of a ketone ends with the suffix “one”.
A number is used to denote the carbon atom on which the carbonyl group is bonded.
The first ketone in the homologous series is therefore propane.
What is the first ketone in the homologous series?
The first ketone in the homologous series is propanone.
What is the general formula for carboxylic acids?
CnH2n+1COOH
How do we name carboxylic acids?
- Select the longest carbon chain containing the
carboxyl group. The -e ending of the parent alkane
name is replaced by the suffix -oic acid. - Aromatic carboxylic acids (i.e., with a CO2H
directly connected to a benzene ring) are named
after the parent compound, benzoic acid.
What is the general formula for an ester?
CnH2n+1COOCmH2m+1
How do we name esters?
What is the general formula for amines?
CnH2n+1NH2
What is the name of the functional group of aldehydes?
Aldehydes have the carbonyl functional group at the end of their carbon chain.
What is the name of the functional group of ketones?
Ketones are molecules which contain the carbonyl functional group in the middle of the carbon chain.
What is the IUPAC system?
International Union of Pure and Applied Chemistry system for the standardised naming of organic compounds.
What is the functional group of nitriles?
A nitrile is an organic compound consisting of an alkyle group with a cyanide group (-CN) attached to it.
What is a cynaide group?
The cynaide group consists of a carbon atom and a nitrogen atom linked by a triple covalent bond.
What is the empirical formula?
The empirical formula shows the simplest whole number ratio of the elements present in one molecule of the compound. For example emeprical formula of glucose is CH2O.
What is a molecular formula?
The molecular formula shows the actual number of each type of atom in a molecule. For example the molecular formula of glucose is C6H12O6.
What is the structural formula?
The structural formula shows how many, and the symbols of, atoms bonded to each carbon atom in an organic molecule. The structural formula of propane: CH3CH2CH3
The structural formula of propene:
CH3HC=CH2
(c-c double bonds are shown in structural formula)
How can we calculate molecular formula using emperical formula and relative molecular mass?
Example:
Mr=42 and Emperical formula=CH2.
Divide Mr by Emperical formula. 42/14=3
Multiply emperical formula by 3= C3H6
What is the displayed formula?
The displayed formula shows a 2D representation of an organic molecule, showing all its atoms (by their symbols) and their bonds (by short single, double or triple lines).
What is a skeletal formula?
The skeletal fomula is a simplified displayed formula with all C-H bonds removed.
What is an aliphatic structure?
An aliphatic compound is a straight chain or branched chain organic compound and also include cyclic compounds that do not contain a benzene ring.
What are alkynes?
Alkynes are hydrocarbons which contain carbon-carbon triple bonds. Their general formula is CnH2n-2 for molecules with one triple bond (and no rings)
What is an aryl compound?
An aryl compound contains at least one benzene ring.
What is a benzene ring?
A benzene molecule has 6 carbon atoms arranged in a hexagon, with each carbon atom bonded to one hydrogen atom. The carbon atoms are linked by bonds that alternate between single and double bonds,
What is a saturated hydrocarbon?
Saturated hydrocarbons are hydrocarbons which contain single bonds only resulting in the maximum number of hydrogen atoms in the molecule.
What is an unsaturated hydrocarbon?
Unsaturated hydrocarbons are hydrocarbons which contain carbon-carbon double or triple bonds.