Organic Chemistry First Test – Flashcards
Unlock all answers in this set
Unlock answersquestion
What is Organic Chemistry? |
answer
-the study of compounds derived from living organisms. |
question
What is the problem with "Vital Force"? |
answer
Synthesized urea had the exact same properties as urea from natural sources. According to vitalism, these compounds would not be similar, but modern thought has concluded that both compounds are exactly the same. |
question
What is The Octet Rule? |
answer
atoms transfer or share electrons in such a way to attain a filled shell of electrons. |
question
Ionic Bonds: |
answer
-The attraction of two oppositely charged particles. -ionic compounds are composed of an anion (-’ve) and a cation (+’ve) that are attracted to one another |
question
Covalent bonds: |
answer
bonds that are formed from the sharing of 2 electrons and the overlap of orbitals. |
question
What is a hetero-atomic bond? |
answer
-An unequal sharing of the electrons can occur to provide polar covalent bonds. -Unequal electron distribution about a molecule results in a dipole moment. |
question
What is a Formal Charge? |
answer
The charge of an atom within a Lewis Structure (basically what is the difference in number of e- for a free atom vs. the atom in a structure). Formal charge= [group #] - [nonbonding atoms] - 1/2 [shared electrons] |
question
What type of molecules are usually Ionic? |
answer
Acids and Bases |
question
What is Resonance? |
answer
The actual structure. -Only e- can be transfered. |
question
What is the 's' orbital defined as? |
answer
a standing wave (trident) that simply vibrates up (+) and down (-). |
question
What is the 'p' orbital defined as? |
answer
a standing wave (trident) that is separated by a node and the two halves vibrates up (+) and down (-) out of phase. |
question
Molecular Orbitals (overlapping) |
answer
Two atomic orbitals overlap to form two molecular orbitals: 1) Bonding molecular orbital (lower energy) – Which we will discuss 99.9% of time 2) Nonbonding molecular orbital (higher energy) |
question
What is sigma bonding? |
answer
-Electron density is centered directly between nuclei -These are single bonds or the first bond of a multiple bond |
question
What is pi bonding? |
answer
-Results from the overlap between two p oribtals with electron density above and below bond axis -These are the 2nd or 3rd bonds of a multiple bond -‘Sideways overlap’ |
question
What are the General Rules of Hybridization? |
answer
1. Both sigma bonding e- and lone pair e- can occupy hybrid orbitals. – The number of hybrid orbitals is computed by adding the number of sigma bonds to the number of lone pair e- on the atom. 2. Use the hybridization and geometry to provide the largest amount of space for the e-. – sp (2 areas of e- density; 180o; Linear) – sp2 (3 areas of e- density; 120o ; Trigonal) – sp3 (4 areas of e- density; 109.5o ; Tetrahedral) 3. If 2 or 3 pairs of e- form multiple bonds, the first of the bonds is a sigma bond, formed by the overlap of a hybrid orbital; the 2nd and 3rd bonds are pi bonds and come from the overlap of unhybridized p orbitals. |
question
What does Polarizability do? |
answer
It tends to increase with molecular weight and also depends on molecular arrangements (isomers). |
question
What are Dipolar Forces? |
answer
attractive force that exists between the positive end of one polar molecule and the negative end of the other. |
question
What is Hydrogen bonding? |
answer
attractive dipolar forces between molecules in which hydrogen atoms are covalently bonded to very electronegative elements (O, N or F). |
question
How does one define a `general alkane`? |
answer
-ALL SINGLE BONDS |
question
What's the name of the alkane that only contains 1 carbon? |
answer
methane |
question
What's the name of the alkane that only contains 2 carbons? |
answer
Ethane |
question
What's the name of the alkane that only contains 3 carbons? |
answer
propane |
question
What's the name of the alkane that only contains 4 carbons? |
answer
butane |
question
What's the name of the alkane that only contains 5 carbons? |
answer
pentane |
question
What's the name of the alkane that only contains 6 carbons? |
answer
hexane |
question
What's the name of the alkane that only contains 7 carbons? |
answer
heptane |
question
What's the name of the alkane that only contains 8 carbons? |
answer
octane |
question
What's the name of the alkane that only contains 9 carbons? |
answer
nonane |
question
What's the name of the alkane that only contains 10 carbons? |
answer
decane |
question
First Rule of IUPAC |
answer
Determine the longest continuous chain of carbon atoms in molecule. -This is the base name (i.e. hexane, pentane, butane, etc.) -When two choices are available, choose the main chain with the highest number of substituents. |
question
Second Rule of IUPAC |
answer
Number the carbon atoms in the longest chain, beginning with the end of the chain nearest a substituent. |
question
Third Rule of IUPAC |
answer
Any substituent connected to the longest chain is named as the alkyl (-ane -> -yl) group and the location of this substituent is provided by the number of the carbon on the main chain it is connected to. • This is the name for the branch (i.e. hexyl, pentyl, butyl, etc.) |
question
Forth Rule of IUPAC |
answer
When two or more substituents are present, list them in alphabetical order. When two or more of the same alkyl substituents are present, use the prefixes di-, tri-, tetra-, etc. to avoid having the same alkyl group twice. |
question
What are the two conformations of Alkanes? What are the three positions they can be in? |
answer
- Sawhorse Structure & Newman Structure -Eclipsed, Straggered, or Skewed |
question
What is the most stable conformation for cyclohexane? |
answer
the `chair` form |
question
What is a`Resonance HYBRID`? |
answer
A single Lewis Structure that cannot completely describe a compound. |
question
What is the `Major Contributing Structure`? |
answer
The structure that is the lowest in Energy , filled octets, and least formal charge/ |
question
What is an Arrhenius Acid/Base? |
answer
Acid- substance that provides H+ Base- substance that provides OH- |
question
What is a Bronstead-Lowry Acid/Base? |
answer
Acid- a species that can donate a proton (H+) Base- a species that can accept a proton (H+) |
question
pH=? [H+]=? |
answer
pH=-log[H+] [H+]=10^-pH |
question
When discussing Acid Strength, the "___" the pKa, the "___" the acid. |
answer
When discussing Acid Strength, the "LOWER" the pKa, the "STRONGER" the acid. |
question
Ka=? |
answer
Ka=[H+][A-]/[HA] |
question
What are the three factors that are used to predict Acid Strength? |
answer
1) Electronegativity 2) Anion Size 3) Resonance |
question
Define Lewis Acids/Bases. |
answer
Acids- accepts e- pairs to form bonds. Bases- donates e- pairs to form bonds. |
question
What is an `Electrophile`? |
answer
Lewis Acid- "lover of e-" |
question
What is a `Nucleophile`? |
answer
Lewis Base- "Lover of the Nucleus" |
question
What are Isomers? |
answer
different compounds that can be formed with the molecular formula. |
question
What is a Steroisomer? |
answer
isomers that differ only in the arrangement of atoms in space. |
question
Define Solubility. |
answer
"Likes Dissolve Likes" |
question
What are `Alkenes`? |
answer
-CONTAIN DOUBLE BONDS |
question
What are `Alkynes`? |
answer
-TRIPLE BONDS |
question
What are `Aromatics`? |
answer
hydrocarbons with very stable bonding. |