Chapter 21 - Organic and Biochemical Molecules Flashcards
What is a hydrocarbon?
A compound that contains mostly hydrogen and carbon.
What is an alkane? Are they saturated? What is their formula? What type of reactions do they undergo?
Contain compounds with only C-C single bonds
Can be represented by the formula CnH2n12
Are said to be saturated because each carbon present is bonded to the
maximum number of atoms (4)
The carbon atoms are described as being sp3 hybridized
Substitution reactions
What is an alkene? What type of isomerism do they undergo? Reactions?
Contain one or more C-C double bonds
Simplest alkene is C2H4 (ethylene), which is described as containing sp2
hybridized carbon atoms
Restricted rotation about the CPC bonds in alkenes can lead to cis–
trans isomerism
Undergo addition reactions
What are alkynes? What type of reactions do they undergo?
Contain one or more C-C triple bonds
Simplest example is C2H2 (acetylene), described as containing
sp-hybridized carbon atoms
Undergo addition reactions
What are aromatic hydrocarbons? What reactions do they undergo?
Contain rings of carbon atoms with delocalized p electrons
Undergo substitution reactions rather than addition reactions
What are alcohols?
Contain hydroxyl group (-OH)
Replace e in the end of parent hydrocarbon name with -ol
Named based on the number of R groups attached:
1 = primary, 2 = secondary, 3 = tertiary
What are aldehydes and ketones?
Contains carbonyl group (C–O)
Carbonyl attached to two carbon groups in ketones
Carbonyl attached to at least one hydrogen in aldehydes
Ending for ketone: -one
Ending for aldehyde: -al
What are carboxylic acids?
Contain carboxyl group ( carbon double bonded to oxygen and single bonded to hydroxyl)
Ending: -oic acid
What are esters?
Contain a carbonyl (C–O) and alkoxy (R-O) group at same carbon
Base name on carbonyl group
-oate
What are amines?
At least one N-C bond
Named based on how many are present (primary, secondary, tertiary)
prefix: amino
What are amides?
Contain a carbonyl and an amino group on the same carbon
-amide
Why is carbon such an important molecule?
Forms strong bonds and has high BDE
Normal valence = 4
Good at forming pi bonds
What is catenation?
The ability of a chemical element to form extended chain-like structures via a series of covalent bonds. Carbon has the highest propensity of all elements for catenation because…
- Strong C-C bond dissociation energies
- Intermediate electronegativity (therefore relatively low bond polarities)
o Higher polarity = less stable
- Strong s-p mixing to allow AO hybridization and strong pi-bonding interactions
Define constitutional isomers and provide examples
contain different patterns of bonding
o Structural isomers – same chemical formula, different bonding patterns
o Positional isomers – same carbon skeleton and same functional groups, but in different positions
o Functional isomers – same chemical formula, different functional groups
Define stereoisomers and provide examples
contain same patterns of bonding, but in different spatial orientations
o Geometric isomers – contain the same atoms and bonds, but are oriented differently in a way that cannot be interchanged (i.e., not conformers)
Cis and trans isomers
o Optical isomers (Enantiomers) – molecules that are mirror images of each other, but that cannot be superimposed
