Brønsted and Lowry designated an acid as a ______ _____ and a base as a ______ _____. Acidity and basicity are usually measured in ______ in which the acid ______ _____ and forms _______ ions and the base _____ ____ forming ______ (from those ions)
- proton donor
- proton acceptor
- donates protons
- hydronium ions
- removes protons
Water itself is ______ (as far as pH is concerned). It forms an equal number of _______ & ________ ions by ____-______
- hydroxide & hydronium ions
Through self ionization, the process of water's dissociation is understood through the equation: H2O + H20 ⇋ H30+ + OH-
How would you describe water's equilibrium constant Kw as a function of this equation? What is the value of the hydroxide concentration?
- Kw = [H3O+][OH-] = 10-14mol2L-2
- [OH-] = 10-1mol*L-1
What is the equation for the pH of [H3O+]?
pH = -log[H3O+]
The acidity of general acid (HA) is expressed by the equation:
HA + H2O ⇌ H3O+ + A-
How would you derive the equilibrium constant?
K = [H3O+][A-]/[HA][H2O]
In dilute aqueous solution, [H2O] is constant at 55 mol L-1, so this number may be incorporated into a new constant, the acid dissociation constant Ka. What is the equation?
Ka = K[H2O] = [H3O+][A-]/[HA]mol*L-1
The pKa is the pH at which the acid is _____ ______. An acid with a pKa lower than 1 is defined as _____, and one with a pKa higher than 4 is defined as ______. What is the equation for pKa?
- 50% dissociated
- pKa = -logKa
Sulfuric acid and the hydrogen halides (with the exception of HF) are ______ acids, while Hydrogen cyanide, water, methanol, ammonia ad methane are _____ acids
The species A- is the ______ _____ of HA and HA is its _______ ______.
- conjugate base
- conjugate acid
The strengths of two substances that are related as a conjugate acid-base pair are ________ _______. So the conjugate base of a weak acid would be a ______ base and the conjugate acid of a weak base would be a ______ acid
- inversely related
- strong base
- strong acid
The guiding principle for determining the relative strength of an acid HA is as follows: The more stable the ______ _____ aka the ______ its base strength, the _______ the corresponding acid. List 4 factors that affect this.
- conjugate base
- inductive effect
The more electronegative the atom the acidic proton is attached, the more _____ the bond, and the more ______ the proton will be.
The greater the __ _______ of the orbital on an atom bonding with the acidic proton, the more ________ the atom is, because it attracts the ______ in that orbital more strongly. List the hybridizations in order increasing acidity
- s character
The proximity of an atom (A) to another electronegative atom (or atoms) also _______ A- and increases the _______ of the proton bonded to A. This property derives from the transmission of the _______-attracting power of the additional electronegative atom(s) through the bonds in the molecule and is termed the _______ _______
- inductive effect
The acid strengths of the hydrogen increases in order of larger A-, because the the overlap of the larger _____ _____ orbitals with the 1s hydrogen orbital is poor which ______ the H-A bond. In addition, the larger ____ _____orbitals permit the electrons to occupy a _______volume of space, thus ______ electron-electron repulsion in the resulting anion.
- outer shell
- outer shell
_______ in A- allows delocalization of charge over several atoms. This effect is frequently enhanced by the presence of other ________ atoms in A-. For example, we can compare this effect in methanol and acetic acid. Methoxide, the conj. base of methanol has ____ resonance forms and a _______ negative charge around oxygen. However, acetate has ____ resonance forms and a ________ negative charge around oxygens.
In general, acidity increases to the ______ and ______ while basicity increases to the ______ and _____
- Lewis acid: species with an atom at least two electrons short of a closed outer shell
- Lewis base: has at least one lone pair of electrons
A Lewis base shares its ____ _____(s) with a Lewis acid to form a new _______ bond. We depict this by the arrow being drawn from the ______ to _____
- lone pair(s)
- covalent bond
- base (lone pair) to acid
Keep in mind the H+ in solution is stated as H+ for convenience, it always associated with a Lewis basic species such as a molecule of _______
All nucleophiles are _____ ____, they are often abbrvtd. Nu, and may be ______ charged or ______ but all of them contain at least one ______ ______. All Lewis acids are ________.
- Lewis bases
- lone pair
Keep in mind species like HCl and CH3Cl are not Lewis acids because they have _____ outer shells. However, they may still behave as electrophiles, because they possess _____ _____ that impart electrophilic character to H in HCl and C in CH3Cl
Organic compounds possessing carbon-halogen bonds are called ________. The carbon-hydrogen bond often makes them behave like ________
Two features of functional groups
- sites of comparatively high chemical reactivity
- control reactivity of the molecule as a whole
Hydrocarbons have the general empirical formula ______. Those with only single bonds such as methane and ethane are called ______. Molecules such as cyclohexane, whose carbons form a ring are called ________.
Alkanes lack ______ groups and as a result are relatively ______ & _____
- functional groups
- nonpolar & unreactive
Benzene and its derivatives are traditionally called _______ because some substituted benzenes do have a strong fragrance, they are also called ______.
Be able to recognize/draw the following: alkane, alkene, alkyne, alcohol, ether, thiols, haloalkane, aldehyde, ketone, carboxylic acid, anhydrides, esters, amides, nitriles, amines
The carbonyl functional group C=O, is found in ______, ______ and in conjunction with an attached -OH, in ______ _____.
- carboxylic acids
We commonly use the symbol R to represent an ______ ______
Substances consisting entirely of single-bonded carbon and hydrogen atoms and lacking functional groups are called _______. They are classified into several types according to structure: the linear ______-____ alkanes; the _______ alkanes
- straight-chain alkanes
- branched alkanes
Straight-chain alkane series follow the formula _________. While branched chain alkanes follow the formula _________, they are said to be ________ _______ of straight-chain alkanes.
- H-(CH2)n-H (n is the number of carbons)
- constitutional isomers
For alkane homolgs > 4 there are more than ____ ______ possible.
List straight chain alkanes 1-20
Prefixes like sec, tert, etc are used to classify the _____ _______ carbon atoms in organic molecules. A primary carbon is one attached to a _____ carbon atom. All hydrogens bound to primary carbons are ______ hydrogens
- sp3 hybridization
Primary can be found at the end of ______ chains or when an alkyl group is created by removing a primary _______. A secondary carbon is attached directly to ____ _____ carbon atoms, and a tertiary carbon is attached to ______ ______ carbon atoms. Finally, a quatenary carbon bears four ______ _____
- alkane chains
- two other
- three other
- alkyl groups
IUPAC rules (4)
- 1]Find the and name the longest chain in the molecule
- **If a molecule has two or more chains of equal length, the chain with the largest number of substituents is the base stem chain
- 2]Name all groups attached to the longest chain as alkyl substituents
- 3]Number the carbons of the lonest chain beginning with the end that is closest to a substituent
- **If there are two substituents at equal distance from the two ends of the chain, the substituent to come first in alphabetical order is attached to the carbon with the lower number
- 4]Write the name of the alkane by first arranging all the substituents in alphabetical order (each preceded by the carbon number to which it is attached and a hyphen) and then adding the name of the stem