Chapter 2: Chemical Level of Organization

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subatomic particles

- Compose atoms. - Three relevant kinds: neutrons, protons and elections

What are the 3 common liquid mixture solutions?

1. Colloid 2. Solution 3. Suspension

What are the 2 representations of the structure of an atom

1. In the electron cloud model of an atom, the shading represents the change of finding an electron and regions outside the nucleus. 2. The electron shell model, filled circles represent individual electrons, which are grouped into concentric circles according to the shells they occupy.

What are the two principle classes of compounds?

1. Inorganic Compounds 2. Organic Compounds

Inorganic Compounds

1. Lacks carbon and structurally simple 2. Their molecules only have a few atoms and cannot be used for by cells to perform complicated biological functions. 3. Inorganic Compounds include water and many salts, acids and bases. 4. Inorganic Compounds may have either Ionic or covalent bonds 5. Water makes up 55-60% of a leans adult's total body mass, all other inorganic compounds combined add 1-2%. 5. Inorganic compound that contains carbon include -carbon dioxide:CO(2) -bicarbonate ion: HCO(3-) -carbonic acid: H(2)CO(3)

What are the 5 types of chemical Reactions?

1. Synthesis reaction-Anabolism 2. Decomposition Reaction-Catabolism 3. Exchange Reaction 4. Reversible Reaction 5. Oxidation-Reduction Reaction

Organic Compound

1.Organic Compounds always contain carbon, usually contain hydrogen and always covalent bond. 2. Most are large molecules, many made up of long carbon atom chains. 3. Organic compounds make up the remainin 38-43% of the human body.

How many can each electron shell hold?

1st Shell: 2 electrons maximum 2nd Shell: 8 electrons maximum 3rd Shell: 18 electrons maximum

Bond Symbols

===== ingle covalent bond ===== ===== double covalent bond ===== ===== triple covalent bonds ===== This applies to both covalent bonds with the same element and covalent bonds with different elements.

Mixture

A combination of elements or compounds that are physically blended together but not bound by chemical bonds. Ex: the air that you are breathing in is a mixture of gases that includes: nitrogen, argon, and carbon dioxide. The three common liquid mixtures are: solution, colloids and suspensions. Once mixed together, the solute in the solution remains dispersed among the solvent molecules. Because the solute particles in a solution are very small, a solution looks transparent.

Concentration

A measurement of how much solute exists within a certain volume of solvent

Suspension

A mixture in which particles can be seen and easily separated by settling or filtration. Ex. Blood is an example of a suspension. When freshly drawn from the body the blood is reddish in color evenly. Overtime the red blood cell settle out of the suspension and drift to the bottom of the test tube. The upper layer, the liquid portion of the blood appears yellow and is called blood plasma. Blood plasma is both solution of ions and other small solutes and colloid due to the presence of large plasma protein.

Solution

A mixture that forms when one substance dissolves another. Ex: Lemonade=water+Lemon water (solvent) + lemonade mix (solute)=lemonade (solution)

Compound

A substance that consist of atoms of two or more different elements. Most of the atom in the body are joined into compounds. Ex: Water=H2O = 2 Hydrogen +Oxygen Sodium Chloride=NaCL=Na (sodium) + Cl (chloride)

Solute

A substance that is dissolved in a solution. Ex: Lemonade=water+Lemon water (solvent) + lemonade mix (solute)=lemonade (solution) Solutes that are charged or contain polar covalent bonds are hydrophilic.

Solvent

A substance that would dissolve all other materials. It is a liquid substance that would dissolves the Solute. Ex: Lemonade=water+Lemon water (solvent) + lemonade mix (solute)=lemonade (solution)

Types of Chemical Reaction Facts

After a chemical reaction occurs, the atoms of the reactant are re-arranged to produce a product with a new chemical properties. There are 5 types of chemical reactions.

Metabolism

All chemical reaction occurring in the body.

Matter

All living and nonliving things consist of matter.

Electron Shells

Although subatomic particles does not have a specific path they follow within the space, the same groups of electrons will most likely move within certain regions around the nucleus. These are known as Electron Shells. They are depicted as simple circles around the nucleus/

Free radical

An atom or group of atoms with unpaired electron in its outermost electron Shell. Ex: super-oxide which is formed by the addition of an electron to an oxygen molecule. Having an unpaired electron makes a free radical unstable, highly reactive and destructive to nearby molecules. Free radicals become stable by either giving up their unpaired electron or taking an electron from another molecule. The contact with another element in the process of the free radicals giving or taking electrons may break apart important body molecules.

atomic mass (aka atomic weight)

An average mass of all it's naturally occurring isotopes. Typically the atomic mass of an element is close to the mass number of it's abundant isotope.

Covalent bond with different element

An example of covalent bond occuring with 2 different atoms is the gas methane (CH4). Carbon has the atomic number of 6 therefore it has 4 electrons on it's valence shell. In order to fulfill the rule of octet it will need 4 electrons. Hydrogen which only has 1 electron will require another 1 more electron to complete it's valence. If you add 4 hydrogen with the carbon, then all 4 hydrogen atoms will be stable as it now has 2 electrons on it's valence and the Carbon atom will have 8 electrons total, 4 of those electrons were shared by the hydrogen.

Electrolytes

An ionic compound that breaks apart into positive and negative ions in solution. Most ions in the body are dissolved in body fluids as electrolytes so named because their solution can conduct an electric current.

Where does ionic compound exist?

As solid, with orderly repeating arrangement of the ions as in a crystal of NaCl. A crystal of of NacL may be large or small-the total number of ions van vary but the ratio of Na+ to Cl- is always 1:1. Ionic bonds exist in teeth and bones where they give great strength to these structural tissues.

Temperature

As temperature rises, particles of matter move about more rapidly. Thus. the higher the temperature of matter. the more forcefully particles will collide, and the greater chance that a collision will produce a reaction.

Isotopes

Atoms of the same element that have different numbers of neutrons. Its still the same element, just a different version. Ex: Carbon Carbon has 6 protons and 6 neutron during it's stable state. This original version would be, Carbon 12. Mass Number =12 The second version is Carbon 13 as it contains 6 protons and 7 neutron. Mass number 13 The third version is Carbon 14, as it contains 6 protons and 7 neutrons. Mass number 14 By the looks of this protons remains the same however, the neutron number changes. Although the isotopes of an element has different numbers of neutrons, they have identical properties because they have the same number of electron. Most isotopes are stable which means that their nuclear structure doe not change overtime.

Activation energy facts

Because particles of matters such as atoms, ions and molecules, have kinetic energy, they are continuously moving and colliding with one another. A sufficiently forceful collision can disrupt the movement of valence electron causing an existing chemical bond to break or a new one to form. The collision energy needed to break the chemical bond of the reactant is called the activation energy.

HCO3-

Bicarbonate inorganic exception

Catalyst Facts

Chemical reaction occurs when chemical bonds break or form after atoms, ions or molecules collide with one another. Body temperature and the concentration of molecule in body fluids, however are far too low for most chemical reaction to occur rapidly enough to maintain life. Raising the temperature and the number of reacting particles of matter in the body could increase the frequency of collision and thus increase the rate of chemical reaction, but doing so could also damage or kill the body's cell. Substance called catalyst solves this problem.

Major Elements (4)

Constitute about 96% of the body's mass. Oxygen-65% Carbon-18% Hydrogen-9.5% Nitrogen-3.2 %

Trace Elements

Constitute for 0.4% of the body's mass. Several trace elements have important function in the body. Aluminum (Al) Boron (B) Chromium (Cr) Cobalt (Co) Copper (Cu) Flourine (F) Iodine (I) Manganese (Mn) Molydenum (Mo) Selenium (Se) Silicon (Si) Tin (Sn) Vanadium (V) Zinc (Zn) Ex: Iodine is needed to make thyroid hormone

Lesser Element (7)

Constitute for 3.6 % of the body's mass Calcium (Ca)-1.5% Phosphorus (P)-1.0% Potassium (K)-0.35% Sulfur (S) -0.25% Sodium (Na)-0.2% Chlorine (Cl)-0.2% Magnesium (Mg)-0.1% Iron (Fe)-0.005%

Decomposition Reaction-Catabolism

Decomposition reaction split up large molecules into smaller atoms, ions or molecules. A decomposition reaction is expressed as follows: AB=A+B Ex: For example, under proper condition, a methane molecule can decompose into one carbon atom and two hydrogen molecule. CH4= C + 2H(2) (balanced) 1 methane molecule= 1 carbon + 2 hydrogen molecule The decomposition reaction that occur in your body are collectively referred to as catabolism. Overall, catabolic reactions are usually exergonic because they release more energy than they absorb. Ex. The series reaction that break down glucose pyruvic acid, with the net production of two molecules of ATP, are important catabolic reaction in the body.

Energy

Each chemical reaction involves energy changes. En=in Ergy=work It is the capacity to do work.

Endergonic reaction

End=within Absorb more energy than they release. In general exergonic reaction occur as nutrients such as glucose is completely broken down. If the molecules in glucose is completely broken down, the chemical energy in its bond can be used to produce as many as 32 molecules of ATP. The energy transferred to the ATP molecule is then used to drive endergonic reaction needed to build body structures such as muscles and bones. The energy in ATP is also used to do the mechanical work involved in contract of muscle movement of substance into or out of cells.

Potential Energy

Energy stored by matter due to it's position. Ex: The energy stored in water behind a dam or a person who is about to jump of a cliff. When the dam is open or the person jumps, the potential energy is converted to kinetic energy.

Reactant

Ex: H2O starting substances H2 and O2

Exergonic reaction

Ex=out Release more energy than absorb. Energy released from an exergonic reaction often is used to drive endergonic one. Ex. In general exergonic reaction occur as nutrients such as glucose is completely broken down. If the molecules in glucose is completely broken down, the chemical energy in its bond can be used to produce as many as 32 molecules of ATP. The energy transferred to the ATP molecule is then used to drive endergonic reaction needed to build body structures such as muscles and bones. The energy in ATP is also used to do the mechanical work involved in contract of muscle movement of substance into or out of cells.

Common Anions in the body

Fluoride Ion-F- Chloride Ion-Cl- Iodine Ion I- Hydroxide Ion-OH- Bicarbornate Ion-HCO3- Oxide Ion O2- Sulfate Ion SO42- Phosphate Ion-PO43-

Hydrogen Bond

Forms when Hydrogen atoms with a partial positive charge (6+) attracts the partial negative charge (6- )of neighboring electronegative atoms, most often larger oxygen or nitrogen atoms. Thus, hydrogen bonds result from attraction of oppositely charged parts of molecules rather than from sharing of electrons as in covalent bonds or the loss or gain of electrons as in ionic bond. Hydrogen bonds are weak In comparison to ionic and covalent bonds, this is why they can't bind atoms to molecules. Although, hydrogen bonds are unable go bind atoms together, they are do establish important links between molecules or between parts of a large molecule such as protein and nucleic acid . the hydrogen bonds that neighbouring water molecule gives water considerable cohesion, the tendency of like particles to stay together. The cohesion of water molecule creates a very high tension , a measure of difficulty of stretching or breaking the surface of the liquid. At the boundary between air and water, the water's surface tension will be greater as the water molecules will be much more attracted to other water molecule than other molecules in the air. Ex: Ants walking on water or a leaf floating on water. The influence of water tension on the body can be seen in the way that increases the work required for breathing. A thin film of watery fluid coats the air sacs of the lungs. So, each inhalation must have enough force to overcome the opposing effect of surface tension as the air sacs stretch and enlarge when taking air. Even though single hydrogen bonds are week, very large molecules may contain thousands of these bonds. Acting collectively, hydrogen bonds provided considerable strength and stability and help determine the three-dimensional shape of large molecules.

What information is conveyed when you write the molecular or structural formula for a molecule

H I Structural Formula: H-H or H-C-H I H Molecular Formula: H2 or CH4 Atomic and Molecular Structure: the one with orbits

Liquid

Has a definitive volume and assumes the shape of a their container. Ex: Blood Plasma.

Hydrophilic

Hydro=water Philic=loving Solutes that are charged or contain polar covalent bond. They dissolve in water easily Ex: most common hydrophilic solutes are salt and sugar

Hydrophobic

Hydro=water Phobic=fearing They are not very water-soluble. Ex: Hydrophobic compounds include animal fats and vegetable oil.

Common Cations in the body

Hydrogen- Ion H+ Sodium Ion-Na+ Potassium Ion- P+ Ammonium Ion -NH4+ Magnesium Ion -Mg2+ Calcium Ion -Ca2+ Iron Ion-Fe2+ Iron Ion-Fe3+

Water in Chemical Reaction Key points.

Hydrolysis-decomposition breakdown of large nutrient molecule into smaller molecule by adding water molecules. Dehydration Synthesis-two or more smaller molecules join to form a larger molecule.

Ion

If an atom either gives up or gains electron it becomes an ion. An ion is an atom that has a positive or negative charge because it has unequal number of protons and electrons.

Water as Solvent

In medieval times people searched for a universal solvent, a substance that would dissolve all other materials. They found nothing that would work as well as water. Although it is the most versatile solvent known, water is not the universal solvent.

nonpolar covalent bond

In some bonds two atoms share the electrons equally, one atom does not attract the shared electrons more strongly than the other atom. Ex. The bonds between 2 identical atoms are always nonpolar covalent bonds. The bond between the carbon and hydrogen atoms are also non-polar (CH4)

What is the most massive element present in human body?

Iodine It consist of 53 electrons. 2 on the 1st shell 8 on the 2nd shell 18 on the 3rd shell 18 on the 4th shell 7 on the fifth shell.

What are the 3 types of chemical bonds?

Ionic Bonds Covalent Bonds Hydrogen Bonds

Ionic bond

Ionic bond is the force of attraction that holds together with opposite charges. Ex: Sodium and Chlorine atoms Sodium has one valence electron, if sodium loses the 1 electron on it's valence, it is left with 8 electron on the 2nd valence which will now become the new valence shell. Now the proton which is 11 now exceeds the amount of electrons which is now 10 as 1 was lost. The sodium atom has become CATION or positively charged ion. A sodium ion has a charge of 1+ and is written as Na+. on the other hand Chlorine has a 17 protons, therefore it only needs 1 more electron to meet the rule of octet in it's valence shell. After gaining an electron, the total numbers 18 exceeds the number of protons which is 17. This mean that the chlorine atom has ANION, a negatively charged Ion. The ionic for of chlorine is chloride ion. It has a charge of 1- therefore it is written as CL-. When an atom of sodium donates it's sole valence electron to an atom of chlorine, the resulting positive and negative charges pull both ions tightly together, forming an ionic bond. The resulting positive and negative charges pull both ions tightly together forming an ionic bond. The end result is sodium chloride. (NaCL.)

Chemical Energy

Is a form of potential energy that is stored in the bonds of compounds and molecules. The total amount of energy present at the beginning and the end of a chemical reaction is the same. Energy/matter can be neither be created or destroyed, it may be converted from one form to another. This is known as law of conservation of energy.

Water

Is the most important and abundant inorganic compound in all living system. You might be able to survive weeks without food, but without water you would die within a matter of days. Nearly all the body's chemical reactions occur in a watery medium. Water has many properties that make it such an indispensable (necessary) for life. For example, it's polarity-the uneven sharing of electron gives a partial negative charge near the one oxygen atom and two partial positive charges near two hydrogen atoms in a water molecule. This property makes water an excellent solvent (a liquid substance capable of dissolving a substance) for other ionic or polar substances, give water molecule cohesion (tendency to stick together) and allows water to resist temperature.

Mass number

Is the sum of its proton and neutrons. Ex. Sodium has 11 protons and 12 neutrons it's mass number would be 23. Although all atoms of one element have the same number of protons, they may have a different number of neutron and therefore different mass number.

How can concentration be expressed?

It can be expressed in many ways. 1. Percentage (mass per volume) This gives the relative mass of a solute found in a given volume of solution. Ex: Alcohol 14.1% by volume, 2. Moles per liter (mol/L) this is called molarity. This relates to the total number of molecules in a given volume of solution. A mole is the amount of any substance that has a mass in grams equal to the sum of the atomic masses of all its atoms. Ex: 1 mole of the element chlorine (atomic mass=35.45) is 35.45 grams and 1 mole of the element chloride (NaCl) is 58.44 grams (22.99 for Na+35.45 for Cl. Just as a dozen always means 12 of something a mole of anything has the same number of particles: 6.023x10(23) The huge number is the Avogadro's number. The measurement of substances that are state in moles tell us about the number of atoms of specific element.

Gas

It does not have a definitive volume or shape Ex: Oxygen and carbon dioxide

Solid

It has a definite shape and volume. Ex: Bone and teeth are compact and have a definite shape and volume.

Synthesis Reaction-Anabolism

It is the process of two or more atoms, ions or molecules combining together to form a new and larger molecule. A synthesis reaction that occur in your body to build up. Overall, anabolic reaction are usually endorgonic because they absorb more energy than they release. Combining simple molecules like amino acids to form a large molecule such as protein as an example of anabolism. Synthesis=to put together Ex: A + B=AB An example of a synthesis reaction between two hydrogen molecule and one oxygen molecule to 2 molecules of water. 2H(2) + O(2)----> 2H(2)O 2 hydrogen +2 Oxygen= Water molecule All of the synthesis reaction that occur in the body collectively referred to as Anabolism.

Law of Conservation of Energy

It's a law that states that energy can neither be destroyed or created but it may be converted from one form to another. Ex. Some chemicals in the food we eat is eventually converted into various forms of kinetic energy, such as mechanical energy that we use to walk and talk. Conversion of from one form to another generally release heat, some of which is used to maintain normal body temperature.

Dalton.

It's a unit of measuring the mass of atoms and their sub-atomic particles also known as ATOMIC MASS UNIT Ex. A proton has a mass of 1.007 daltons or the mass of an electron is 0.0005 dalton, almost 2000 times smaller than the mass of a neutron or proton.

Exchange Reactions

Many reaction in the body are exchange reaction; they consist of both synthesis and decomposition reaction. One type of exchange reaction works like this. AB+CD-----> AD+BC The bond between A and B and between C and D break through (decomposition) and a new bond then form (synthesis) between A and D and between B and C. Ex: HCL + NaHCO(3)----->H(2)CO(3)+NaCl hydrochochloric acid + Sodium Bicarbonate-----> Carbonic acid+Sodium Chloride The ions in both compounds have "switched partners". The hydrogen ion (H+) from HCl has combined with the bicarbonate ion (HCO3-) from NAHCO3 and the sodium ion (Na+) from NaHCO3 has combined with the chloride ion (Cl-) from HCl.

Dehydration Synthesis

Metabolism has two types of metabolic activities CATABOLISM and ANABOLISM Anabolism is the building of a more complex molecules from smaller sub-units. The action of building a more complex molecule requires energy which comes from the break down of ATP. Dehydration synthesis is an anabolic reaction. Water is removed as larger molecules are formed. Through dehydration synthesis larger carbohydrates, fats or lips are formed and it can fuse amino acids together. De=from, down or out Hydra=water

Hydrolysis

Metabolism has two types of metabolic activities CATABOLISM and ANABOLISM Hydrolysis is a catabolic reaction which allows for the larger nutrients to be broken down to a more simple molecule, through the help of adding water. Hydrolysis enables dietary nutrients to be absorbed into the body. Hydro=water Lysis=to loosen or break Ex: through hydrolysis sucrose (table sugar) can be broken down to glucose and fructose Through hydrolysis protein can be broken down to smaller molecules of amino acids Through hydrolysis of fat molecules it can be broken down to smaller molecules of glycerol and fatty acids.

CH4

Methane

How does water dissolve crystal of salt such as NaCL (sodium chloride)

O= has a total of 8 electrons therefore it has 6 in it's valance, to complete the rule of octet it will have to take 2 electron from another molecule. This will give oxygen a -charge H=has 1 electron and to complete the valence it will give it's 1 electron away. This will give H a + charge Na=11 electrons with 1 electron on the valence shell therefore it will give the 1 electron away. This will give Na a + charge CL=has 17 electron with 7 on it's valence which means it will take another electron. This will give chloride a - charge. Due to it's negative and positive charge, NaCl will attract each other (opposites attract) to become Na+CL- however when water is mixed, it will break apart Na+Cl-. Oxygen being a - charge will naturally be attracted to sodium (Na+) and hydrogen being + charge will naturally be attracted to CL as it is -charge.The water molecules that surrounds the ion lessens the chance of Na+Cl- to reform back. The ability of water to form solution is essential to health and survival. Because water can dissolve so many different substances, it is an ideal medium for metabolic reactions. Water enables dissolved reactants to collide and create a new product. Water can also dissolve waste products which allows them to be flushed out of the body in the urine.

Chemical Reaction

Occurs when new bonds are formed an old bonds break between atoms. The interaction of valence electrons are the bases of all chemical reaction.

Triple covalent bond

Occurs when two atoms share three pairs of electrons. This can occur with in a molecule of nitrogen. Nitrogen has a 7 proton, therefore it has 7 electrons. on it's valence it will have 5 elections which means to abide by the rule of octet to be stable it will need 3 more electrons. You can then combine with another Nitrogen atom and both will be stable as they are sharing both of their 3 electrons and it's valence shell now has 8.

Oxidation-Reduction Reaction

Oxidation-reduction reaction are essential to life, since they are reaction that break down food molecules to produce energy. These reactions are concerned with the transfer of electrons between atoms and molecules. Oxidation refers to the loss of electrons in the process, the oxidized substance releases energy. REDUCTION refers to the gain of electrons, in the process the reduced substance gains energy. OXIDATION REDUCTION REACTIONS are always parallel when one substance is oxidized, another is reduced at the same time. When food molecule such as glucose, is oxidized, the energy produced is used by a cell to carry out it's various functions.

26 elements

Produced from natural elements using particle accelerator or nuclear reactors.

Double covalent bond

Results when two atoms share 2 pairs of electons. This happens in oxygen molecule Oxygen has 6 protons therefore 6 electrons. Oxygen has 4 electron on it's valance therefore it needs 4 electron or 2 pairs to abide by the octet Rule, and become stable.

Covalent bond formation.

Single, double and triple covalent bonds the electrons are shared equally. There are also instances when the electrons are unequally shared, therefore the atom may become slightly positive and slightly negative.

Reversible Reaction

Some chemical reaction proceed in only one direction, from reactants to product, which is indicated by 1 arrow. Other chemical reaction may be reversible. In a reversible reaction, the product can revert back to the original reactant. A reversible reaction is indicated by 2 half arrows pointing the opposite directions. AB breakdown into A+B _______________________\ /________________________ combines to form Some reactions are reversible only under special conditions: AB water A+B ______________________\ /_____________________ heat In this case whatever is written above or below the arrows indicates the condition needed for the reaction to occur. In these case reactions AB breaks into A and B only when water is added and A and B react to produce AB only when the heat is applied. Many reversible reaction in the body require catalyst called enzymes, often, different enzymes guide the reaction in opposite direction.

Octet Rule

States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons

What are 2 factors that can influence the cause of particle collision and chemical reaction?

Temperature and Concentration of particles.

Mass

The amount of matter in any object which does not change

Activation Energy

The collision energy needed to break the chemical bond of the reactant. The initial energy "investment" is needed to start a reaction. The reactant must absorb enough energy for their chemical bonds to become unstable and their valence electron to form a new combination. Then, as the new bonds form, energy is released to the surroundings. Both the concentration of particles and the temperature influence the chance that a collision will occur and cause a chemical reaction.

Nucleus

The dense central core of an atom. Within the nucleus it contains: 1. Positively charged protons 2. Uncharged neutrons 3. Negatively charged electrons They all move within the large space surrounding the nucleus. They do not have a fixed path or orbit but instead form a negatively charged cloud that surrounds the nucleus.

Product

The ending substance Ex: the 2 molecules of H2O are the product

Kinetic Energy

The energy associated with matter in motion. Ex: The energy stored in water behind a dam or a person who is about to jump of a cliff. When the dam is open or the person jumps, the potential energy is converted to kinetic energy.

Weight

The force of gravity acting on matter changes. When the objects are farther from the earth, the pull of gravity is weak, this is why the weight of an astronaut is close to zero in outer space.

Chemical Bond

The force that holds together the atoms of a molecule or a compound. The likelihood that an atom will form a chemical bond with another atom depends on the number of electrons in it's utmost shell.

Concentration

The more particles of matter present in a confined space the greater chance that they will collide. Ex: drivers on the street. The more drivers there are on the street the higher the chance of collision. Therefore. the concentration of particles increases when more are added to a given space or when the pressure on the space increases, which forces the particles closer together so that they collide more.

Atomic number

The number of proton in the nucleus in the atomic number. The atomic number is specific to that element.

Electronegativity

The power to attract electron to itself

Chemistry

The science of the structure and interaction of matter.

Polar Covalent bond

The sharing of two atoms is unequal-the nucleus of one atom attracts the shared electrons more strongly than the nucleus of another atom. When polar covalent bonds form, the resulting molecule has a partial negative charge near the atom that attract electron more strongly. This atom has a greater electronegativity which is a power to attract the electron to itself. At least one other atom in the molecule then will have a partial positive charge. The partial charges are indicated by a lowercase Greek delta- 6- or 6+ Ex: the bond between oxygen and hydrogen bond in a molecule of water. In this molecule, the nucleus of the oxygen atom attracts the electron more strongly that do the nuclei of the hydrogen atoms, so the oxygen atom is said to have greater electronegativity. The bond of Nitrogen and hydrogen and the bond between oxygen and carbon are also types of polar bond.

Atom

The smallest unit of matter that retains the properties and characteristics of the element. Hydrogen atom is the smallest atom as it only has one electron. The largest atoms are only 5 times larger.

Cohesion

The tendency of same kinds of particles to stay together.

Radioactive Isotopes

The the more isotopes the more it becomes unstable. The nuclei decay (spontaneously changes) into a stable configuration. As they decay these atoms emit radiation, in the process it transforms into a different element. Ex: The Radioactive isotope of Carbon, C-14, decays to N-14. The decay of a radioisotope may be fast as a fraction of a second or as slow as millions of years. Radioactive isotopes has harmful and helpful effects. The Radiation can break apart molecules which can cause tissue damage or cause various types of cancer. Radon-222, a colorless and odorless gas that can cause lung cancer, this derives from Urianium can can seep through soil and buildings. Some beneficial effect of certain radioisotopes incused their use in medical imaging procedures to diagnose and treat certain disorders. So radioisotopes can be used as tracers to follow the movement of certain substances through the body. THALLIUM-201 is used to monitor blood flow through the heart during an exercise test. IODINE-131 is used to detect cancer of the thyroid gland and to assess it's size and activity and may be used to destroy overactive thyroid gland. CESIUM-137 is used to treat advanced cervical cancer and IRIDIUM-192 is used to treat prostate cancer.

Half-life

The time required for half of the radioactive atom in a sample to decay in to a more stable form. Ex. The half-life of C-14, which is used to determine the age of organic samples is about 5739 years; the half like of Iodine (I-131, an important clinical tool, is 8 days)

Free Radicals and Antioxidants

There are several sources of free radicals, including exposure to ultraviolet radiation in sunlight, exposure to x-rays and some reactions that occur during normal metabolic processes. Certain harmful substances such as: CARBON TETRA-CHLORIDE-a solvent used in dry cleaning) also gives rise to free-radicals when they participate in metabolic reaction in the body. Among many disorders, diseases and condition linked to oxygen derived free radicals are cancer, atherosclerosis, Alzheimer's disease, emphysema, diabetes mellitus, cataract, muscular degeneration, RA and deterioration associated with aging. Consuming more ANTIOXIDANTS substance that inactivate oxygen-derived free radicals is believes to slow the pace of damage caused by the free radicals. Important dietary antioxidants include: Selenium zinc Beta-carotene Vitamin C and E Red, blue or purple fruits and vegetables contain high level of antioxidants.

List the 4 valves in heart in order starting with RA ----> RV

Tricuspid/R atrioventricular = RA to RV Pulmonary/R semilunar = RV to pulmonary trunk Mitral/bicuspid/L atrioventricular = LA to LV Aortic/L semilunar = LV to aorta

Chemical bonds represent stored chemical energy and chemical reaction occurs when new bonds are formed or old bonds are broken atoms. The overall reaction may either release energy or absorb energy. A key feature of body's metabolism is the coupling of exergonic and endergonic reaction.

True

True or False The number of electron in an atom is the same number of proton. Because each electron carries a negative charge and proton carries a positive charge the atom is electrically neutral; it's total charge is 0

True

True or False

True The atoms of each element have a characteristic way of losing, gaining or sharing their electrons when interacting with other atoms to achieve stability. The way that electrons behave enables atoms in the body to exist in electrically charged forms called ions.

true or false

True The versatility of water as a solvent for ionized or polar substance is due to it's polar covalent bonds and its bent shape, which allows each water molecule to interact with several neighboring ions or molecules. Solutes that are charged containing polar covalent bonds are hydrophillic: hydro=water philic=loving-loving. which means that they can dissolve in water easily.

There are 26 different chemical elements present in your body? true or false

True or False

The total mass of the reactants equal the total mass of the product

True. This means that if there are: 4 hydrogen and 2 oxygen on the reactant side the product should also contain 4 hydrogen and 2 oxygen before and after the reaction.

Solvent, Solute and Solution in the body

Usually there is more solvent than solute in a solution. For example: Your sweat is the dilute solution of water (solvent) plus small amounts of salts (solute) =sweat which is the (solution)

Thermal properties of water

Water can be absorb or release a relatively large amount of heat with only a modest change in its own temperature. For this reason water is said to have a high heat capacity. The reason for this is because of the high concentration of hydrogen in the water. The hydrogen bond allows the water molecule to retain heat. Because water absorbs heat energy ex. through boiling, some of the energy is used to break hydrogen bonds. The energy that is left over will increase the motion of water molecule which would increase the water's temperature. The high heat capacity of water is the reason it is used in automobile radiators; it cools the engine by absorbing heat without the water temperature rising to an unacceptable high level. The large amount of body water has a similar affect; it lessens the impact of environmental temperature change, helping to maintain body temperature homeostasis. In a fever situation, if you drink water when your body's temperature is increased, the heat is absorb without damaging the molecular integrity of water. Water also requires a large amount of heat to change from a liquid to a gas. As water evaporates from the surface of the skin, it removes a large quantity of heat, providing an important cooling mechanism.

Water as a Lubricant

Water is a major component of mucus and other lubricating fluids throughout the body. Lubrication is specially necessary in: - the chest -for plueral activity -the heart for pericardial activity -the abdomen for peritoneal activity where internal organs touch and slide over one another. - joints, where bones, ligaments, and tendons rub against one another. Inside the gastrointestinal tract, mucus and other watery secretions moisten good, which aids their smooth passage through the digestive system.

Water in Chemical Reaction

Water serves as the mediums for most chemical reaction in the body and participates as a reactant or product in certain reactions. During digestions, for example, decomposition reaction break down large nutrient molecules into smaller molecules by the additional water molecules. This type of reaction is called hydrolysis. Hydrolysis reactions enable dietary nutrients to be absorbed into the body. By contrast, when two smaller molecules join to form a larger molecule in a dehydration systhesis reaction, a water molecule is one of the products formed.

Molecule

When two or more atoms share an electron. Ex: a molecule may consist of two atoms of the same kind such as Oxygen molecule. The molecular formula for a molecule of oxygen is 02. The subscript indicates that the molecule contains two forms of oxygen. To or more different kinds of atoms may also form a molecule as it in a water molecule (H2O). In H2O one atom of oxygen shares electrons with two atoms of oxygen shares electrons with two atoms of hydrogen. In H2O one atom of oxygen shares electrons with 2 atoms of hydrogen.

Water Tension

a measure of the the difficulty of stretching or breaking the surface of a liquid.

Catalyst

are chemical compounds that speed up chemical reaction by lowering the activation energy needed for a reaction to occur. The most important catalyst in the body are enzyme. A catalyst does not alter the difference in potential energy between the reactant and the product. Rather it lowers the amount of energy needed to start the reaction. For a chemical reaction to occur, some particles of matter especially large molecules-not only must collide with sufficient force, but they must hit one another at a precise spot. A catalyst helps to properly orient the colliding particles. Thus they interact at the spot that makes the reaction happen. Although the reaction has a catalyst helps to speed up a chemical reaction, the catalyst itself is unchanged at the end of the reaction. A single catalyst molecule can assist one chemical reaction after another.

CO2

carbon dioxide inorganic exception

H2CO3

carbonic acid inorganic exception

Colloid

differs from a solution mainly because of the size of it's particles. The solute particle in a colloid are large enough to scatter light, just as water droplets in fog scatter lights from a car's headlight beam. Colloids usually appear translucent or opaque. Colloids also does not settle out and accumulate on the bottom of a container Ex: Milk, fog

Chemical Symbol

each element is represented by a one or two letter Ex: C for carbon Ca for calcium

HCL

hydrochloric acid

Chemical Element

is the limited number of building block for all living and nonliving matter.

Ionization

is the process of giving up or gaining electrons. An Ion of an atom is symbolized by writing it's chemical Symbol followed by the number of positive (+) or negative (-) charges. Ex: Ca P=20 1st shell=2 electron. 2nd shell=8 electron. 3rd shell=18 electron. 4th shell=2 electrons. because Ca is not stable and has 2 electrons on the valance shell, it will give out the 2 electrons to fulfill the octet rule to be stabilized. Because Ca give up 2 electrons it has now turn to Ca2+

92 elements

occur naturally on earth.

Valence Shell

outermost shell of an atom. an atom holding eight electrons is chemically stable which means that it is unlikely to form chemical bonds with another atom. Ex: the noble gases (Neon is an example that has 8 electrons in it's valence shell which means it does not bond easily with other atoms. The valence shell of hydrogen and helium is the first electron shell which holds a maximum of 2 electrons. Because HELIUM has 2 valence electrons this too is stable and does not often bond with other atoms. HYDROGEN on the other hand has only 1 valence electron so it will easily bind with another atom.

Single Covalent Bond

results when two atoms share 1 pair of electron to complete the valence shell. Ex. The molecule of Hydrogen. Hydrogen has 1 proton therefore has one electron on it's valence shell. Unfortunately, as per the rule of octet the first valence,it must have 2 electron to be stable. In order for hydrogen to become stable, it will create another bond with another molecule. It can bond with another hydrogen atom who also has 1 electron. When they share their electron. Together, they both become stable as the valence has 2 electrons.

NaHCO3

sodium bicarbonate

NaCl

sodium chloride

Matter exist in 3 states

solid, liquid, gas

What are the key words to remember in Water as solvent?

solvent-a substance that dissolve another substance ex: water solute-the substance that is being dissolved ex: ice tea mix solution-the end product that solvent and solute makes ex: ice tea hydrophobic-they can't be dissolved by water easily ex: fats and vegetable hydrophilic-They are easily dissolve by water and understanding how water can dissolve many different substance by breaking them apart. Na+Cl- ionic bond can be broken when H2O are mixed in between.

118 elements

the number of elements on the periodic table

True or False The number of electrons of an atom determines its chemical properties. in other words, the number of proton is equal to the number of electron to ensure stability in the atom.

true

Covalent Bonds

two or more atoms share electrons. The atoms form a covalent bonded molecule by sharing 1, 2, or 3 pairs of valence electrons. The larger the number of electron pairs shared between the two atoms the stronger the covalent bond is. Covalent bonds may form between atoms of the SAME element or between atoms of DIFFERENT elements. Covalent bonds are the most common chemical bond in the body, and the compound that results from them form most of the body's structure.


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