CHEMISTRY AND BIOCHEMISTRY
There are two classes of nucleotides in DNA: pyrimidine and purine,
and four nucleotides: cytosine, thymine, adenine, guanine.
Easiest way to remember to which class they belong is that all pyramidines
(cytosine and thymine) contain the letter y.
As well, adenine and guanine are nine-sided molecules,
and the pyramidines are six-sided molecules. See the animation showing how
a six-sided molecule becomes a pyramid.
Separating DNA/RNA
Although DNA and RNA are both nucleic acids, they do different jobs in the
cell. Just remember:
- DNA Delivers the blueprint, RNA Reads it.
- RNA uses Ribose sugar.
- RNA uses uRacil in place of thymine.
SUGARS
Simplified Sugars
There are two simple sugars (monosaccharides) -- fructose and glucose --
which combine in a specific way to form sucrose. Remember the molecule of Fructose has
Five carbons (letter F starts both words) and hexaGon is the shape of the Glucose molecule
(letter G in both words). Remember too, if fructose and glucose attach the
wrong way, you end up with an undigestible fibre instead of sucrose sugar.
Into Insulin
Insulin gets sugar into cells. Without insulin, a person can
have excess sugar in his blood yet die of lack of sugar. Excess sugar is
removed via urine. Romans noticed bees attracted to the urine of diabetics
and coined the term "diabetes" to describe the overflow of sugar.
(literally, diabetes = "across the sugar"). Medical students need
to distinguish between the two types of diabetes: mellitus and insipidus.
Both cause increased urine flow, but for different reasons altogether. D.
mellitus is characterized by excessive sugar present in the urine due to
lack of insulin. D. insipidus is recognized by high volumes of watery urine
due to lack of anti-diuretic hormone (ADH), usually caused by a damaged hypothalamus
gland. In the old days, a physician would taste the urine to determine which
form of diabetes his patient had.
WATER
Capilliary Action
Water rises to the tops of plants by Capilliary Action (CA), which depends
upon Cohesive and Adhesive (C+A) properties of H2O.
Hydrolysis and Monomers
Hydrolysis is the way water can break molecules (hydro=water, lysis=cut).
Certain molecules called monomers (mono=one, mer=water*) have a hydroxide
and a hydrogen attached to the side. When a monomer bonds to another monomer
or polymer, the HO and H atoms break off and combine to form a single water
molecule.
You can see the effects of hydrogen bonds in real life whenever you iron
cotton fabric. Cotton is a long cellulose chain with H-bonds attaching
it to other cellulose chains. When these bonds link out of parallel, we get
wrinkled clothes. Heat and moisture (i.e., steam iron) break and reform these
bonds to a more parallel shape. Wool has covalent and electrovalent
disulfide bonds which can be permanently set (permanently pleated) by breaking
and reforming these bonds with certain sulfur chemicals. Nylon, polyester,
acetate, and triacetate are thermosensitive and their shapes can be heat
set.
* ~mer actually means "piece" in Greek and "sea" in
French, but I found this way makes it easier to remember.
Osmosis Sucks
To remember how osmosis works, remember that "Particles suck." Thus,
tonicity (hypertonic, hypotonic) refers to concentration of particles, and
water always goes toward the area of more particles.
(from: Hallie Ray, Science Department, Rappahannock Community College,
Warsaw, VA)
Two Easy Bonds
Two easy bond angles are also two of the more common ones we need to memorize.
Sure, it is hard to remember which molecules have what angles, but it is
important if you want to make any money as a chemist of any note.
The H2O molecule is bent because the extra electron cloud sticking
out of the oxygen atom pushes the two hydrogen atoms away, thus making an
angle of 105 degrees instead of a straight line. Similar thing with NH3,
except the electron cloud pushes against the three hydrogens to modify the
regular tetrahedral shape a bit. To be precise, the angle between the hydrogens
and the central nitrogen is 107 degrees. How do I know this? Because I count
the letters in WATER and AMMONIA and come up with 5 and 7 respectively
(to correspond with 105 and 107 degrees respectively).
TABLE OF ELEMENTS
Although reports have surfaced of people committing the naturally occurring
elements to memory simply by reciting the symbols as a crazy sentence that
starts "Hy! He libeb cnof nenam gal sips clark casa tiv crmn feconi
cuzn gage ass ebr krrb styz rnb mot crurh pdag ..." we will refrain
from attempting something so dangerous. Instead, I present the following:
2nd Period Elements
Like Being Bare Cuz Naked Orgasms Feel Neat for lithium, beryllium,
boron, carbon, nitrogen, oxygen, fluorine, neon. Or the more risque Lithesome
Beryl Blows Charlie Nightly On Floor Neeling.
3rd Period Elements
Once you see this word pattern in the third period (Na, Mg, Al, Si, P, S,
Cl, and Ar) you'll always remember that Nagging Maggie Always SiPS ClAret.
4th Period Elements
PoKey Captain Scans Tight Virgin Crew Members Fer Cold Night Cuddles.
Zany Gray Germs Are Sold By Kremlin, or in reverse order: Kry
Brother! SeAs of Germany and Gaul Sink Copper ships Nice and Cold from
Manx to Crimea, Vancouver to Timor, and Scandinavia to the California Koast.
5th Period Elements
Rub Strong Young Zulus. Nubile Mona Touches Ruth's Rectum. Pallid Agents
Could Infiltrate Tiny Stubborn Telephone Industry Xecutives.
6th Period
This row on the left lower portion of the table contains Cesium, Barium,
Lutetium, Hafnium Tantalum, Wolfram (tungsten) and Rhenium. Just remember: Cheap
beers lure half-tanked wolf and rhino. The rest of them might go Osir:
pretty awful hag throws pretty bad polkas all right for osmium, iridium,
platinum, gold, mercury, thorium, lead, bismuth, polonium, astatine, radon.
Another: Osir, platinum-blonde Audrey hogs Thor, plumbs Bill, and polos
at random.
The Lanthanides
Elements #57-71 have two cute mnemonics: Little Cute People Need Plenty
Sex Every Given Time Despite having Enough Through Young Love and Currently
Parties Never Provide Sexy English Girls That Drink Heavily, Even Though
You Look.
Actinides
Berkelium, Californium, Einsteinium, Fermium, and Mendelevium are a snap
when you recite: BlocKheads Can't Find ElementS FroM Mnemonic Devices
Earth's Abundant Elements
Only Silly Asses In College Study Past Midnight tells me that the
most common elements of the planet's crust are, in descending order: oxygen,
silicon, aluminum, iron, calcium, sodium, potassium, and magnesium.
HONC if you like Life!
Of course, H-O-N-C are the four elements that make life's building blocks
-- hydrogen, oxygen, nitrogen, and carbon.
All the Periodic Groups
All 18 groups (columns) of the periodic table are mnenomicized here in order:
- He Likes Naked Kisses and Rubs Cuz he's French or He Licked
Sonja's Krotch, Rubbed Cassy's Front, or Hi LiNa: Kare to Rub
and Copulate like the French do?
- Beryl Might Call Strong Barry, or Betcha Maggie Can Stretch
Balls Rapidly (ouch!) or Being Magnificent Can Sure be Radical.
- ScantY Ladies Acting
- Tight Zipper or Titz're a Handful
- Vixens Nubile and Tantalizing
- Cro Magnon Women Sag or ChroMo Tongue (silver tongued)
- Men Touching Repulsive Nuns
- Feel Ruth Oscillate
- Cold Rhoda Irritates Me
- Nipples Pull Playfully or Nick's a Pal, worth his weight in
Platinum.
- Cum Again, Auuuuu!
- Zena's a Cold Hag or Zinc-plated Cadillacs and Mercury's
- Boinking All Gals In Theatre, or Big Al Gazes Into Telephone or Boning
Al GaIns Thelma
- Carl's Silent, Gena Snores Loudly, or Can Silly Gena Tin Plums? or Car
Sick Germans in Tiny Pub
- Nighties and Panties Are Still Big ... Nice Phurry Ass, Stubby
Beard ... or Nice People As Stubborn Bitches or Nights
Flossing for Arsholes and Bigots
- Ox Sells Sex To Poles or Odie Smith Selling Telephone Poles
- Feeling Clara's Brassiere, I Attack
- He Never Argues or Kries eXcept when it Rains
Bonus The metalloids mnemonic is: Big Sized Genitals Assure
Teasing Stories.
Tip: memorize groups I and VIII, and one period to start. Whenever I need
to sketch out the Periodic Table, I write down the first and last groups,
add the periods that I know, then fill in the blanks using what I've written
down as a guide.
ATOMIC THEORY
Prostitutes & One-eyed Cats
Here's a phrase for remembering atomic properties: Prostitutes Outnumber
Nice Electioneers. Number of protons = atomic number (PROstitutes outNUMBER),
neutrons determine isotope (NIce), and electrons determine ionization (ELECT-IONeers).
Also, Cat Lost an Eye is good for knowing that cations are atoms
which lost an electron.
Skiing the Quantum Ski Hill with Shapely PAM
Some students find it hard recalling the letters designating atomic energy
levels. Originally, they were named after qualities seen in spectroscopy
and later associated with electron energy level. Thus, the qualities of sharp,
principle, diffuse, and fundamental (s, p, d, f) have no relation to electrons.
Nevertheless, my chem prof taught us to Ski Powder Deep and Fast.
Use PAM to remember the three quantum numbers: Principle, Azimuthal, Magnetic
spin. Another one is to think of an Arab publisher: Azim Prints a Magazine.
Furthermore, PAM has a More Shapely Sizin' where MORE = magnetic
orientation, N = size, and l = shape of electron orbits.
Atomic Mazda
Dave, a once-in-a-while bright student, was sitting next to me doing his
quantum calculations which involve the Planck constant -- 6.626 x
1034. I told him the number from memory, he asked me how I knew
it. I asked "how many letters are in Planck's name? " (6), then
I said "Planck drove an older Mazda sedan (a 626), and his 34th birthday
had a negative effect on him." He chuckled and groaned. Twenty minutes
later, he said "John, I can still remember that number".
Rydberg's Colorful Equation
Easy to remember that Rydberg's Equation is used to analyze spectra ... "RYDBERG" contains
most of the colors of the rainbow: red, yellow, dark blue, orange, green.
That formula is: 1/lambda = R(1/n1 squared minus 1/n2 squared)
ABCs of GAS LAW
The ABCs of gas law are Avogadro, Boyle, and Charles. Each contributed a
variation to the standard PV=nRT equation (Perfect Virgins are Not Real Things)
for calculating gas pressure, volume, mass, and temperature. Easy to remember
who came up with which law -- they were all sick! Avogadro was ugly
(his face had a number of moles); Boyle had high blood pressure due
to diabetes; Charles ran a temperature.
A fourth scientist, Gay Lussac, contributed his formula for calculating
variations in temperature and volume whilst pressure was constant. In fact,
Lussac, Boyle, and Charles all can be remembered by their individual formulae
relating to Gas Law:
- BOYLE. The absolutely worst place on your body to get a skin eruption
(boil) is on the penis. Right? So what does this have to do with chemistry?
Well, when you think of your penis, think of Boyle and the fact that diabetics
are constantly peeing to realize Peeing Virtually Constant can be written
as PV=C.
- CHARLES. As a television salesman, Charles didn't do so well. That's
why he got into chemistry. He is best remembered for saying any TV is as
good as another ... and expressed it mathematically as T1V2=T2V1.
- GAY LUSSAC. Gay had once tried selling tents to native indians near
Quebec City before answering a newspaper ad for a chemist. His two-for-one
sales pitch is still recited by Iroquois as T1P1=T2P2.
REACTION MECHANISMS
As the Molecule turns ... SN1, SN2 Reactions
The only way I could remember the differences between SN1, SN2, E1, E2 reactions
were to make up stories about what I imagine is happening. If you don't think
you'll enjoy this story, then go to the Virtual
Chem Page and click on Organic Synthesis to see animations of SN1, SN2.
Substitution reactions come in two flavours: slow (SN1) and quick (SN2).
They produce different products in differing ratios as well. While in lecture,
I thought the nucleophile sounded like a paramour, and the leaving group
was a loser in the deal, and if those molecules were people, they would be
on a soap opera. So, I doodled and came up with names that relate to the
reaction and are easy to remember. There are more details, but for now, let's
just read a couple of short stories to get the general idea of each.
SN1 (Soap Network 1) is suffering low ratings. It was supposed
to be a hot show but it is pretty slow. The scene: On an aeroplane (airplane to
Americans) Levi and Nel are having a boring breakfast together. Nel poured
some alcohol (a polar - protic solvent) into his coffee then told
him to take a hike. As Levi was the pilot anyway, he left. Luke, a stowaway,
then came along to woo Nel. "I'm too cold" she said, but
Luke was looking at her huge bum and realized that type of hindrance would
really slow things down, and that he would have to have a few intermediate
steps along the way. Besides, the room for error would mean half the
children might be born racemized. While Luke wanders around trying
to decide is he should come in through the back door or be conventional,
Nel just plays with the feline she calls Carbo-cat. When she and
the cat double up and bond, Luke is eliminated.
SN2. To get ratings back, Soap Network 2 was launched. A more racy
script with competent actors and director, this show really socks it to
them. All three characters have had their apathy replaced by three new
psychological disorders. Nel has Electra complex, which is a real
plus; Drew is in denial, and Luke suffers proto-Oedipus complex.
Nel's emotionally bipolar; her emotional energy rises as
Drew gets ready to leave then peaks the moment he walks out the front door
and Luke enters the same door disguised as a television repair man. Their
affair is quick and passionate, but always inverted. As time
went on, some of Nel's sons consumed some anabolic hormones and managed
to beat the crap out of Luke whenever he came around. This is called the Steric
Effect.
Clinduction
Refer to the adjacent picture for clues to the five ways of changing acidity
of a molecule.
- N is for the nitrogen at the top that is more electronegative
than carbon. Thus a hydrogen attache to nitrogen is more acidic.
- H is for the hydrogen bond between oxygen and hydrogen. H is also
for the hybridization of the carbons on the left side.
- 3 are the bonds between the two sp hybridized carbons.
- OH! Resonance.
- Clinduction is chlorine's induction force on the structure. (Cl-induction)
Chemical Tidbits
- Cis looks like lips puckered for a kiss.
- Trans looks like a train ran over those lips.
- Conning Old Prelog means Cahn-Ingold-Prelog Sequence Rules, with
one rule for each name.
- Newman and Fischer Projections are useful but confusing. I remember Newman
projections are two superimposed circles, because MAD magazine's Alfred
E. Neuman has a round face. Fischer projections use a cross, and so I think
Emil Fischer was Christian.
- The Nitrogen Bonding Nitrile compounds have Nitrogen in a triple
bond with carbon.
From
A very nice site of Anatomy Mnemonics by John Berger
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