Study Guide for Anatomy and Physiology - Use With an Open Text !

CHEMISTRY (Chapter 2 of Marieb textbook, see pg. 24, Text)

Atoms - building blocks of matter, smallest units of matter indivisible by chemical means.
Elements - composed of like atoms.
Molecules - composed of two or more atoms, H₂ is a diatomic molecule, but also units of the
element Hydrogen (H).
Compounds - composed of like molecules, each of which has two or more different kinds of
atoms.

Hydrogen - the building block of the universe

The simplest atom is common Hydrogen  See below: Protium, atomic mass or weight
of 1, has 1 proton and one electron. There are two other, rarer, forms of Hydrogen:
Deuterium (mass=2) and Tritium (mass=3). They are called isotopes (different forms
according to mass but with the same atomic numbers) of Hydrogen because they all
have one positive proton and one negative electron. All unreacted or uncombined
atoms have # protons = # electrons to create a 0 electrical charge. How many
neutrons does Protium, Deuterium and Tritium have?
 

X-rays, gamma rays and ultraviolet rays are mutagenic; that is, they mutate DNA,
the chemical in our cells that carries the messages of inheritance that regulate cell growth,
reproduction and metabolic activities. See  http://en.wikipedia.org/wiki/Gamma_ray

Why wear "sun screens?"

See: http://www.epa.gov/radiation/docs/ionize/ionize2.htm,
http://www.cpc.ncep.noaa.gov/products/stratosphere/uv_index/uv_nature.html
and http://www,epa.gov/radiation/students . Click on What is Radiation,
Types of Radiation;

Some medical Imaging techniques use forms of radiation produced by decaying atomic
nuclei. Some forms are more dangerous than others. In general, short wavelength forms
have very high energy and can therefore mutate the chemical of inheritance, DNA, and
cause cancers or the death of cells.

In radiation therapy, beams of gamma rays are focused on a tumor to 'burn out'
the cancer cells. One goal of physicians has been to lower the dosage of medical imaging
x-rays or gamma rays which patients are exposed to during their lifetime. Recently,
a breast cancer gene (causative in 10% of all breast cancers) has been discovered that  is
activated by x-rays.

If food is bathed by gamma rays (as in sterilization/preservation), does that make the food
radioactive?

To study the radiation effects of the atomic bombs dropped on Japan, see
http://www-sdc.med.nagasaki-u.ac.jp/n50/disaster/medical-E.html
 

Are there any medical procedures or treatments which do not have risk?
 
 

Is it contradictory that x-rays are used to treat cancer but that they can cause cancer?
 
 

Hydrogen fusion (proton chain) powers the Sun:

Einstein discovered that Mass (an amount of matter, on Earth designated as weight) can be
converted to energy. Some mass is converted to energy in the Fusion reaction.

Remember, Einstein said:

E = mc² , m=mass, c=speed of light (300,000 meters per second).

Some heavier atoms are cooked up in stars, such as Carbon, Iron, Silicon, Nitrogen, Sulfur,
Phosphorus, Aluminum, Copper, et c. Since these atoms are in our tissues, Carl Sagan calls us
"Star Stuff." There are several types of energy which are important for Environmental Sciences.
Atomic energy is stored in atoms, it literally holds the atomic nucleus together.
When atoms are split (as in an Uranium or Plutonium fission bomb or nuclear reactor)
or fused (as in the Sun or laser fusion devices)some mass is converted to energy.

Kinetic energy is the energy that moves atoms or molecules.
Kinetic energy provides the energy to collide reactants A with B to react to make C product.
Heat increases molecular motion.

Why is it easier to dissolve corn starch or table salt in warm water rather than cold water?

Chemical energy is stored in chemical bonds. Radiant energy (travels in waves, see
above) and electrical energy (carried by moving electrons) will be considered in this course. .

Periodic Chart: Look up element #19 in the periodic chart in Appendix D.
Here is #12 as an example.  See also http://www.webelements.com . Also see p. 26, text.
 
 

2 8 2

12 Mg 24.3

(numbers at left represent electron configuration 1st shell = top #)

We will deal with small-medium size atoms. With the Periodic Chart Handout, or information
included, you should be able to draw Hydrogen (H), Helium (He); Sodium (Na); Chlorine (Cl);
Carbon (C) and Oxygen (O). Keep in mind that the first electron shell (K) contains a maximum
of 2 electrons: the second 8: the third 18 (M) etc. Mendeleev discovered that, after Helium that
has 2 electrons, every eighth (increasing atomic mass units) element were inert or
unreactive, they will not normally combine with other atoms to make molecules. This is called
"The Rule of Octets or Eights." The modern interpretation is that after Helium,
nonmetal atoms with eight (8) electrons in their outermost shell are inert. See
pg. 29.

Draw the following atoms. Include the correct number of protons, neutrons and electrons in
their shells.

                    H                         He                         Ca
 
 
 
 
 
 

                    Na                        Cl                         C
 
 
 
 
 
 

                    N                         O
 
 
 
 

                    Ne, for example:

                 10 +           K(1)         L(2)         M(3)
                         10 n            2e^-            8e^-                 0
 

 See: http://rex.nci.nih.gov/ Click on Radioactive fallout. Then click on press release of I-131 fallout
from nuclear bomb testing. How is I-131 different from I-127? See the map of I-131 exposure, etc.
 

Using webelements, identify the Sr 90 as an isotope. What periodic chart column is it in? It is a relative
of ___________found in bones.

If one eats plants that have soaked up I-131, Sr-90 and Cs-137, does one's radioactivity
level increase?
 

Chemical Bonds

The reason why atoms react or combine to form molecules is that in reacting, they reach a more
stable outer shell electron arrangement, 8, the magic number for atoms stability (and lower
energy level). See p. 33-39.

Ionic bond - If a Na gives away an electron to Cl which keeps it, notice that both atoms have 8
electrons in their outer shell. Now Na⁺ has a +1 electrical charge because it lost one negative
electron and; Cl^- has an extra electron and thus has a -1 negative charge. Charged atoms are
called Ions. See page 35//34 of Text. Ionic bonds are formed when atoms give away or receive
electrons. When atoms lose electrons , an oxidation results, if atoms gain electrons , they
undergo reduction;

Na⁰ ---> Na⁺ (+) 1e^- (Oxidation of Na); Cl⁰ + 1e^- ---> Cl^- (Reduction of Cl)

Nonmetals generally have 4-8 electrons in the outer shell hold on to their electrons and
generally "grab for more". Metals are weak electronegative atoms mean that the atoms which
give up electrons readily; i.e., Metals generally have 1-3 electrons in their outer shells .
Look at your periodic chart. Are Li, Na, K, Mg, Al and Au (gold) metals? _____ How about S, O,
Cl and Ar. What are they, metals or nonmetals? _____

If you dissolve the ionic compound NaCl in water, Na+ and Cl - ions will float free and  be surrounded by spheres of water molecules. See page 42//41.

NaCl -----> Na + (+) Cl -

Solutions of ions are called electrolytes, the presence of which we will see is essential for
the operation of muscle and nerve cells.

Covalent bonds share electrons. Two electrons form a pair and share an orbital path; there
are two shared electrons in one covalent bond represented with a dash . See page 36//35, Oxygen
and Nitrogen. Notice all carbon atoms share 4 bonds (8e^- ).

There are two kinds of covalent bonds:

Nonpolar Covalent, where electrons are shared equally by all atoms, e.g., Methane, CH₄

                       H
                        |
                H -- C -- H;      O=C=O is Carbon dioxide
                              |
                       H

Both of these heavy gases of our atmosphere, along with SO₂ and  NO₂ , contribute to the
greenhouse effect - abnormal warming of the earth (global warming) is thought to occur when these gases,
which concentrate close to the earth's surface, trap heat energy (infra-red radiation) . CH₄ is
also an ozone layer destroying gas. The ozone (0₃ ) layer is thought to protect the earth from
harmful ultraviolet waves which are thought to mutate DNA in skin cell and cause skin cancer.

Nonpolar bonds cannot normally form ions (electrically charged atoms) because they continue
to share electrons. Electrons must be given away and retrieved to form ions.

Polar Covalent bonds have at least one atom which is an electron "bully"; the highly
electronegative atom (usually Oxygen) has a greater share of the negatively charged electrons. .

Because H--O--H is polar as a molecule, meaning that the Oxygen side of the molecule has a
negative charge and the Hydrogen side has a positive charge. This characteristic helps water
dissolve NaCl or table salt. See pg. 36-37.
 

Water Molecule:
 
 

            O-         Water Molecules stick to each other
         /  \          with weak hydrogen bonds. The positive
       +H   H+       and negative ends of water molecules attract each other.

                O-
         /  \
           +H   H+

WATER as a Chemical/Molecule/Substance. See page 40.

Characteristics:

1. Water is Wet! It will dissolve or disperse many substances.

1. Solution - the solid portion or gas (called solute) particles are very small (atoms or
molecules), liquid (usually water) is the solvent. There is more solvent than solute in
a solution. Solutions are transparent to light and the solute will not settle out, e.g.,
NaCl in water.
2. Colloid - larger particles that do not settle out but will scatter light (Tyndall Effect), e.g.,

coffee. Some colloids, importantly those in cells, can change from the sol (liquid) to
gel (solid) states. This occurs in amoeboid movement.
3. Suspension - still larger particles which will be affected by gravity and thus settle out,

e.g., clay in water.
4. Emulsion- mixture of an oily substance and water, e.g.., mayonnaise, homogenized milk.

In the intestine, large pools of fat are broken into small droplets. This is an important process
for the digestion of fats in the intestines.

1. Water sticks to itself: It is cohesive. Because of the polar covalent nature of water,

electronegative oxygen atoms will attract or pull on the positive Hydrogen atoms of
adjacent water molecules, creating weak hydrogen bonds between water molecules.
This makes water hard to boil for it's low molecular weight of 18 (2H @1 each =2,
1 -0 @16 =16).

Some important facts related to water's cohesion are as follows:

1. Water boils at 100 degrees C, Acetone with a molecular weight of 58, boils
at 58 degrees C!
2. To raise the temperature of 1 gram of water, 1 degree C, requires 1 calorie of energy

(heat). To vaporize 1g of water at 100 degrees C requires an additional 540 calories
(heat of vaporization) to break Hydrogen bonds. Water requires a lot of energy input
in order to boil (vaporize).
3. Water has a high specific heat (1 Calorie/1 degree C/1 gram) which means that it

will store heat and thus it acts as a moderator of climate in the summer. The Earth is
also warmer in the Winter because oceans release stored heat.

1. Because water molecules bond to each other, the ones on the surface draw inward
(hydrogen bonding) toward their fellow molecules down below. This creates a film-like
surface or surface tension on which certain water bugs walk.
2. Water is Adhesive; it will stick to certain other substances.
3. Water will adhere to the inside walls of small hollow tubes such as capillaries which
are the smallest of blood vessels. This is called capillarity - it helps to draw blood
into capillaries that serve tissues with nutrients.
4. Water will adhere to hydrophilic (water loving) atoms or atom groups such as, Ions,

strongly electronegative atoms like Oxygen, Nitrogen, et c.. Some substances which are
filled with nonpolar covalent bonds, like oils and fats, are hydrophobic (water fearing).
They are repelled by water.
5. Water is most dense at 4 degrees C. If it warms up or cools off from 4 degrees C,
the water molecules begin to move away from each other. Therefore, solid water formed
at 0 degrees C, ice, has less density (weight/volume) than liquid water and it floats.
6. Water makes a very small but equal number of H + and OH - ions (10 -7 or one 10
millionth of a Mole each).
7. Pure water is a poor conductor of electricity unless you dissolve ions in it. Generally covalent
compounds are poor conductors. Ionic solutions are called electrolytes and are necessary for
the operation of the nervous system.
8. Water, combined with proteins and phospholipids in mucus and serous secretions, is a
lubricant.

Anecdote

A freshman at Eagle Rock Junior High won first prize at the Greater
Idaho Falls Science Fair, April 26. He was attempting to show how
conditioned we have become to alarmists practicing junk science and
spreading fear of everything in our environment. In his project he
urged people to sign a petition demanding strict control or total
elimination of the chemical "dihydrogen monoxide."

And for plenty of good reasons, since:

1. it can cause excessive sweating and vomiting
2. it is a major component in acid rain
3. it can cause severe burns in its gaseous state
4. accidental inhalation can kill you
5. it contributes to erosion
6. it decreases effectiveness of automobile brakes
7. it has been found in tumors of terminal cancer patients
  



ACIDS AND BASES - See pg. 41-43.

Acids are substances which produce H⁺ ions in solution, they are proton donors . For example,
HCl is a polar covalently bonded gas molecule but when dissolved in water makes H ⁺ ions and Cl ^-
ions. Because more molecules of HCl ionize (about 96% generally), HCl (found in our stomach)
is a strong Acid, However, H ₂CO₃ , Carbonic acid, is a weak acid because only about 3% of it's
molecules ionize when in water solution. Carbonic acid is weak; it is found in carbonated
beverages and your blood! An important point is: the more H⁺ ions, the more acid is present.
Are H⁺ ions also protons? ________

100 HCl (in H₂O) yields ---> 96 H⁺ ions + 96 Cl ^- (Chloride) ions: 96 of 100 HCl molecules
break into ions.

100 H2 CO3 (in H2O) yields ---> 3H+ ions + 3HCO3- (bicarbonate) ions;
3 of 100 H2CO3 molecules break up.

Bases are the opposites of acids, or have OH^- ions, or will bond to H⁺ ions/protons. For
example, if a solution had a lot of H⁺  ions, you could add OH^- ions, react the two and form
HOH or water. NaOH or lye is a common base used for making soap and cleaning sink drains.
Bases are opposites of acids, they may make OH^- ions, all will bond to H⁺ ions/protons.
For example, if a solution had a lot of H ions, you could add OH^- ions, react the two and form
HOH or water. NaOH or lye is a common base used for making soap and cleaning sink drains,
e.g., NaOH (in H₂O) ---> Na ⁺ (+) OH ^- Any compound which produces OH^- is a base.
But is NH₃ (Ammonia) a base because NH₃ + H ⁺ ---> NH₄⁺ (The answer is yes!)

Bases react with acids to produce water or Acid + Base ---> Salt and H₂ O
This is called neutralization.

e.g.,

H+ + OH- ---> H2O;  HCl + NaOH ---> NaCl + H2O

Measure of Acidity

pH is an inverse logarithmic scale of H⁺  ion concentration in Moles per liter of solution.
Mathematically, pH=1/log H⁺ ion concentration in Moles/liter. Because the formula is 1 over
the concentration of H⁺ ion, as H⁺ ion conc. increases, pH decreases and vice versa. The pH scale
runs from 0 to 14. A pH of 0 to just below 7, means the solution is acidic and has more H⁺ ions
than OH^- ions. Above 7.00 means a basic solution where OH - is more concentrated than H⁺ .
Note: the scale at first look, appears backwards or if the pH number is high,
H⁺ concentration is low; if the pH # is low, H⁺ concentration is high! A
simple rule which relates to our study of the metric system in lab is a pH = 0 means H⁺
concentration is 10⁰ or 1 mole/liter. A pH of 1 means H⁺ = 10 ^-1 mole/l. A pH of 7 means H⁺ =
10 ^-7 mole/l. Is 10 ^-7 a big quantity or a very small quantity?

Remember: Acid (+) Base yields Salt (+) Water. This is neutralization. The pH will be 7 if it
was a complete neutralization with equal amounts of H⁺ and OH^- resulting.

At a pH = 7, H⁺ conc. = OH^-conc, or 10^-7 Moles H⁺ = 10^-7Moles OH^- .

This buffer pair is found in the blood: H₂CO₃ (a weak acid) and the basic salt of a weak acid,
NaHCO₃ . The weak acid neutralizes bases and the salt neutralizes acids. Identify the acid and base
in NaH₂P0₄ /Na₂HP0₄ , NH₄⁺ /NH₃ , NH₂---/---COOH^- .

pH Scale

( H⁺ ) = hydrogen ion concentration; (OH^- ) = hydroxide ion concentration

Hint: since pH numbers are log rhythmic, log of the number 1 = 0, log of 0.1 = -1;
log 0.01 = -2, log .001 = -3, etc.

Important Measurements and Figures

Mole = the atomic masses of atoms in a molecule added and converted to grams (above).

1 Mole has Avogadro's Number of Molecules or, to be exact, 6.02 x 10²³ molecules-a
huge number!

1 Mole of any compound has Avogadro's Number of Molecules. 2 Moles have
2 x Avogadro's Number of Molecules.

1 liter of water = 1000 milliliters = 1000 cubic centimeters (cc) = 1000 grams = 1
kilogram (kg).

1 gram = 1000 milligrams (mg = 1,000,000 micrograms (ug) =
1,000,000,000 nanograms (ng).

Exponents and Decimals

100=10⁺² 10^-1 = .1 10^-2 = .01 10 ³ = .001 10^-4 = .0001 10^-5 = .00001

10^-6 = .000001 10^-9 = .000000001 10^-10 = .0000000001

Examples of Use:

Organic Chemistry - the chemistry of the Carbon atom. See p. 43 of text.

The simplest organic molecule is CH₄ or methane (above, nonpolar covalent compound).

Major Organic Chemicals -Learn to Recognize!

Carbohydrates - combinations of C and H₂O or C_n(H₂0)_x . See page 44 of text.

Sugars - the most basic energy storing food material of cells is glucose, C₆H₁₂O₆ .

Glucose, fructose and galactose are also C₆H₁₂O₆ or have the same number of atoms, but
they have different structures. For that reason they are called isomers. Glucose, fructose and
galactose are also monosaccharides, one sugar 'link.' Fructose is sweeter than table sugar
(sucrose), which is sweeter than glucose. Glucose is "blood sugar," the basic food material of cells.

Why do cells need glucose and oxygen? To make ATP! See below.

Disaccharides - are composed of two monosaccharide building blocks or monomers. They are
formed by dehydration synthesis - water is removed when the two monosaccharides are
joined to make a larger molecule. See pg. 45 of text.

sucrose - a disaccharide of glucose and fructose, formed by dehydration synthesis.
Breaking the glycosidic bond, as occurs in digestion,  is the enzyme assisted,
opposite reaction of hydrolysis.

maltose - disaccharide of glucose formed with alpha glycosidic bonds.

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lactose - a disaccharide of glucose and galactose.

Polysaccharides- long chain of monosaccharides, or polymer, formed by dehydration
synthesis of monosaccharide monomers using alpha glycosidic bonds (see disaccharides
above).

Starches - have alpha bonds between long chains of glucose molecules twisted into a coil.
Complex carbohydrates are "branched starches" that have side chains branching off of the 6th
carbon atom. Glycogen (liver or muscle cell starch) is a branched polysaccharide.

Cellulose or food fiber- notice the different bonding pattern (beta glucose bonds). There are two types:
soluble (to some degree) and insoluble. They are thought to interfere with cholesterol absorption.

Lipids - oily compounds that will dissolve in nonpolar solvents. See page 47.

Triglycerides - or neutral fats are composed of 3 monomers of fatty acid and one monomer of
glycerol, an organic alcohol. They are joined by dehydration synthesis making ester bonds.
Unsaturated fats have one or more double bonds between C atoms in the chain of fatty acids.
 
 

What happens to unsaturated fats when they are "hydrogenated" as when vegetable oils are
made in solids for use in "stick" margarines?

Steroids - large compounds composed of 4 rings of carbon atoms. Cholesterol is the building
block of many steroid hormones, like estrogen and testosterone. See pg. 47, fig. 2.15, c.

Proteins - are formed by dehydration synthesis of amino acid monomers to form peptide bonds
and long polymers. See page 49-53. There are the basic structural material of cells. Two
principal types in the body are structural proteins and enzymes (see below).

Proteins have four levels of Structure

Primary -	The precise sequence of amino acid molecules(20 types for cells) is  determined by the "genetic code" in DNA..

This would "read": methinonine-glycine-alanine-phenylalanine-leucine-
tyrosine-histidine-valine.
 
 

Secondary -	Determined by hydrogen bonding within the polypeptide molecule that forms a helix, a cylindrical, rope-like structure.

Tertiary -	Determined by disulfide bonding and the polarity of amino acids that turns the molecule so that it can become globular.

Quaternary -	A combination of more than two separate polypeptides of protein. Hemoglobin has 4 polypeptides joined by an iron (Fe+2 ) atom. See pg. 50.

Enzymes - See pg. 53 of text.

Characteristics:

1. Enzymes reduce the energy of activation for a given chemical reaction .
2. All enzymes are proteins . Therefore they can be denatured by heat, acids or other chemicals.

The globular protein shapes of enzymes are changed by heat into stringy solid forms
(like cooking an egg white). Remember, "a boiled egg won't hatch a chicken."
3. Enzymes bond on to their specific substrates by a Lock and Key Process. The

substrate bonds into a specific spot on the enzyme called the active site.

Enzymes participate in both constructive (anabolic, as in making proteins) reactions
and destructive (catabolic, as in digesting proteins) reactions.

1. Enzymes are Catalysts, they generally speed up or regulate reactions: they are not

used up in a reaction. Manganese dioxide is an inorganic catalyst (but not an enzyme)
for the breaking down of hydrogen peroxide. Catalase is a protein catalyst (enzyme)
for the breaking down of hydrogen peroxide.

1. Each enzyme has a  pH range of action. Consider the pancreatic enzyme Trypsin

that digests protein in the small intestine, it operates best at pH of 8 - slightly basic.

However, Pepsin, first secreted in the stomach glands as the protein pepsinogen,
Must bond with H⁺ ions in order to have any activity in digesting protein. In this case
H⁺ ions are cofactors for the Pepsin enzyme.

ATP - the source of most chemical energy stored and used in cells. It is made
in the mitochondria of cells.

ATP stands for adenosine triphosphate (see pg. 57 of text). It is composed of
the DNA nucleotide adenosine and three high energy-bonded phosphate groups.
Chemical energy is stored when ATP is formed from adenosine diphosphate (ADP),
energy from high energy electrons, and one phosphate. Energy is released when ATP
is broken down into ADP and a low energy phosphate.

Each succeeding high energy phosphate bond stores more
energy!

DNA - the chemical of inheritance is significant because it can replicate exactly (with the help of enzymes) and it can direct the synthesis of structural, gene regulatory and enzymatic proteins. See p. 54-56 of textbook.

-

The building blocks (monomers)  of DNA (deoxyribonucleic acid) are called nucleotides. Each
nucleotide is composed of (1.)  a deoxyribose (5C) sugar, (2.) a phosphate (PO₄^-3) group, and
(3.) a nitrogenous base of 4 kinds: Cytosine and Guanine that bind together with 3 hydrogen
bonds, and Thymine and Adenine that bind together with 2 hydrogen bonds. Adenine and
Guanine have two rings of mostly carbon atoms and are called purines, cytosine and thymine
have one ring and are called  pyrimidines.

Study Questions

1. What is a radioactive isotope? How is it different from the most common form of the atom?
2. What forms of electromagnetic radiation are dangerous?
3. What are the building blocks of sucrose, lactose, maltose, starch, cellulose, glycogen, protein,
neutral fat, DNA, and steroids?  Learn to visually recognize each.
4. Compare and contrast the four levels of protein structure.
5. List and explain 4 characteristics of enzymes.
6. Compare hydrolysis and dehydration synthesis (condensation) reactions. Where does
each occur for starches and proteins?
7. Explain how ATP stores and releases energy.
8. How is the genetic code derived from the structure of DNA?
 
 
 

Biology Practice Test _______________________________
  name
Matching (multiple guess) Hint - use best answer and look at all answers. Don't cross answers out.

___1. Tentative and testable explanation.                                                    a. Einstein

___2. Building blocks of the universe                                                          b. theory

___3. If one neutron was changed to a proton                                             c. hydrogen atoms
 in an atomic nucleus, you would have....

___4. 2 (Helium) or eight electrons in an outer                                             d. hydrogen bonds
atom shell

___5. Discovered Rule of Eights (Octets)                                                    e. sunlight

___6. Discovered that mass can be converted                                             f. Calorie
 to energy

___7. All Carbon atoms have 6....                                                                g. another element

___8. Electrons are given away and received                                               h. stable, unreactive atoms
 by atoms.

___9. Even sharing of electrons                                                                    i. hydrogen ions

___10. 1 mole                                                                                             j. electrons

___11. Amount of energy to raise temperature                                             k. hypothesis
 of 1 g of water 1 degree C.

___12. All acids make...                                             l. ions separate when substance dissolved
-
___13. Makes water hard to boil                                           m. Avogadro's number of particles

___14. Hydrogen fusion occurs to make...                                                   n. Mendeleev

___15. Has substantial evidence, but still                                                      o. nonpolar covalent bonds
 tested
 
 
 

12   X  25.4

 a.  Atoms of element X would tend to give away//share//receive (circle one) electrons

 when reacting with another atom with 6 electrons in its outer shell.

 b. T or F. X is a metal.______

 c. X has _______ (#) electrons?

 d. Most X atoms have _______ (#) neutrons?

 e. T or F. Some X atoms weigh 26 or more. _______

Fill-in (1 point each)
Pure Aluminum foil would represent a __________ because all it's atoms are the same.
However, the anti-acid Gaviscon has Al(OH)₃ which is composed of more than one
species of atom and therefore is a __________. An Aluminum ion, Al⁺³, has an electrical
charge because it __________ (gained or lost, choose one) the subatomic particles called
__________. Any atom called Aluminum must have __________ protons in it's nucleus.
((Look up Al on your periodic chart or see  http://www.webelements.com )).

True or False (Believe It or Not!)

____  1. All Scientific Laws remain hypotheses that can be retested.

____  2. The diatomic molecule of Hydrogen is also a compound because it is
composed of more than one atom.

____  3. All Hydrogen species have one neutron.

____  4. Ion atoms have their # of protons = # electrons.

____  5. When the ionic compound NaCl is formed, Na(Sodium) gives
away an electron to Cl(Chlorine).

____  6. A pH of 1 is twice as concentrated in H+ ions as a pH of 2.

____  7. Pure water is a good conductor of electricity.

____  8. Solid ice is less dense than liquid water.

____  9. Helium gas is very explosive.

____ 10. Since Chlorine is an element found in the compound table salt (NaCl),
as a pure element it is harmless.

Short Discussion
1. Why are covalently bonded compounds generally poor ion formers. (2 points).
 
 
 

2. In what 2 ways is water considered to be an unusual compound as compared to
compounds of similar molecular weight? (2 points)
 

3. Explain why doesn't Neon Chloride or metalic Sodium exist in nature.
 

4. Why is I-129 a radioisotope?

5 . What is radon gas?  Describe it as an atom, a radioactive isotope,
its source and hazards.

List

1. List and define 4 types of mixtures. (4 points)

  a.______________________________________________________________

  b.______________________________________________________________

  c.______________________________________________________________

  d.______________________________________________________________
 
 

jaliff @ gpc.edu