Concepts of Matter and Energy

By: Kirstin, James, Ryan David, and Chloe

Matter• Matter- is anything that occupies space and has

weight• Matter can be found in 3 forms• Solid, liquid, and gas• Solids- have a definitive shape and volume• Liquids- have a definitive volume but they conform

to the shape of their container• Gases- have neither a definitive shape nor volume• Matter can have both physical and chemical

changes• A physical change does not alter the basic nature

of the substance• A chemical change do alter the composition of the

substance

There are 2 types of energy

• Kinetic- energy doing work

• Potential- inactive stored energy

• All living things are built of matter to live and function

Forms of energy

• Chemical energy- stored in bonds of chemical substance

• Electrical energy- movement of charged particles

• Mechanical energy-is directly involved in moving matter

• Radiant energy-travels in waves, the electromagnetic spectrum

Energy forms conversions

• Energy can go from one form to another quickly.

• Energy can affect body temp. And also the bodies functioning.

• When your body heats up is can be a form of Kinetic energy

• This chemical reactions in your body is what keeps you alive and functioningeveryday.

Composition of Matter

Mackenzie, Rolanda, Sam, and Jared

Elements and Atoms

• Matter is composed of a limited number of substances called elements.

• Cannot be broken down, • Total 112 elements, 92 naturally and the rest artificially.• Periodic table is where the complete listing of elements appear.• The atom is the building block of elements and all have atomic

symbols on them to show the differences.

Atomic Structure

• Atoms have unique properties• Protons, electrons, and neutrons, and electrical charge• Protons =positive charge• Electrons= negative charge• Nuetrons=neutral charge• Electrical charger= able to attract and repel all the different

properties.• Which all this together in one atom weighs at 1 atomic mass unit.

Planetary and orbital models of an Atom

• Planetary model portrays the atom as a miniature solar system.• Orbital model the more modern model of the atomic structure.• The atomic nucleus includes the protons and neutrons • The nucleus is dense and positively charged• The elements orbit the nucleus• The orbital's are the regions around the nucleus where you would

find the electrons.

Identifying elements

• Protons, neutrons, and electrons are all a like.• Atoms of different elements= have different electrons,

protons, and neutrons• All known atoms can be described by adding one proton

and one electron.• Light protons have equal number of protons and

neutrons larger have more neutrons then protons.

•

Atomic number

• All elements have an atomic number• Atomic number is equal to the number of protons its

atoms contain.• Each atom has different number of protons than atoms

of any other element. • Protons are always equaled to the number of electrons. • The atomic number indirectly tells the number of

electrons the atoms has.

Atomic Mass Number

• Atomic mass number of any atom is the sum of the protons and neutrons contained in its nucleus

• ( EX. Hydrogen has one bare proton and no nuetrons. So its atomic number and atomic mass number is the same which is 1)

Atomic Weight and Isotopes

• Atomic weight is the average of the mass numbers of all the isotopes of an element.

• Isotopes have the same number of protons and electrons but vary in the number of neutrons they contain.

• Radioistopes are havire isotopes of atoms that are unstable and tend to decompose to become more stble.

• Radioactivity is the process of spontaneous atomic decay. It can be compared to a tiny exposions

• Isotopes of an element have the same atomic number but different atomic masses.

• The atomic weight of an element is approximately equal to the mass number of its abundant isotope

Michael MoussalliPatrick McGinn

Sydney O’Connor

Molecules and Compounds

Pages 32-33

Definitions

• Molecule – When 2 or more of the same atoms combine chemically

• H + H H2 (Molecule)

• Compound – When 2 or more different atoms bind together to form a molecule

• 4H + C CH4 (Compound)

Molecular Formula

• The formula that shows what different atoms make a molecule or compound

• H + H

• 2H + O

Chemical Equation

• The whole equation

• H + H = H2

• 2H = O = H2O

Chemical Bonds and Chemical Reactions

Abby, Kristina, Nick, and Kenneth

What is a Chemical Reaction?

• A chemical reaction occurs when atoms combine or separate from other atoms.

Bond Formation

• Chemical bonds are not physical structures.

• They are energy relationships that involve interactions between electrons of reacting atoms.

Roles of Electrons

• Electron shells- (energy levels) fixed regions of space around the nucleus where electrons are found.

• These shells are numbered 1 to 7, starting from the nucleus outward.

• The currently known maximum number of electron shells is seven.

• The closest to the nucleus are the most strongly positive charged.

• The more distant are more likely to react with other atoms(less securely held).

Roles of Electrons (Cont.)

• Each shell has a limit to how many electrons it can hold. (Shell 1 can hold 2, shell 2 can hold 8, etc.)

• Valence Shells- the outermost shell in the atom. It determines the chemical behavior of the atom.

• The electrons in inner shells do not participate in bonding.

Ionic Bonds

• Ionic bonds form when electrons are completely transferred from one atom to another.

• They gain or lose electrons during bonding.

• This causes their positive and negative charges to become unbalanced which result in ions, charged particles.

Ionic Bonds (Cont.)• Negatively charged ions are called anions.• Positively charged ions are called cations.• Both result when an ionic bond is formed.• Most bonds formed under ionic bonds fall under the

category of salts.

Covalent Bonds

• Covalent bonds occur when covalent molecules share electrons.

• In some covalent molecules the electrons are shared equally between the atoms of a molecule. These are called Nonpolar Covalently Bonded Molecules.

• When covalent bonds are made, the molecule formed always has a definite three-dimensional shape. (PG 35)

• The shape determines what other molecules or atoms in can interact with.

• The shape may also result in unequal electron-pair sharing.

Covalent Bonds (Cont.)

Hydrogen Bonds

• Hydrogen bonds are extremely weak bonds formed when a hydrogen atom bound to one electron-hungry nitrogen or oxygen atom is attracted by another electron-hungry atom.

• The hydrogen atoms form a bridge between the atoms.

• Hydrogen bonds are common in water molecules (surface tension).

• Hydrogen bonds also can be called Intramolecular bonds. These bonds help to bond different parts of the same molecule together into a special three-dimensional shape.

Patterns of Chemical Reactions

• Chemical reactions involve the formation or destruction of bonds between atoms.

• There are three types of chemical reactions:

• Synthesis• Decomposition• Exchange

Synthesis Reaction

• A synthesis reaction occurs when 2 or more atoms combine to form a larger more complex molecule.

A + B AB• Synthesis reactions always involve bond

formation.• They are energy-absorbing reactions.• Synthesis reactions underlie all anabolic activities

that occur in body cells.• They are important for growth and repair of old tissue.

Decomposition Reaction

• A decomposition reaction occurs when a molecule is broken down into smaller molecules, atoms, or ions.

AB A + B• Decomposition underlie all catabolic

processes in the body cells.• Decomposition Reactions are basically

Synthesis Reactions in reverse.• Bonds are always broken and the products of the

reaction are smaller.• Chemical energy is released.

Exchange Reaction

• Exchange reactions involve both synthesis and decomposition reactions, both bonds are made and broken.

• A switch is made during the reaction between molecule parts.

AB + C AC + B and AB + CD AD + CB

Biochemistry: The Chemical Composition of Living Matter

Ann Marie Dean, Brett Foxworth, Casey Gurlaskie, Chase Williams

2 major classes of molecules in the body:

•Inorganic and Organic1.Inorganic compounds: Lack Carbon; tend to be small and simple-ex: water, salts2.Organic compounds: Carbon-containing compounds; more complex-ex: carbohydrates, lipids, proteins, nucleic acids

Inorganic Compounds

A. Water

• Most abundant in the body (2/3)

• Properties that make water so vital:1. High heat capacity- absorbs and releases large amounts of

heat before its temperature changes appreciably

2. Polarity/solvent properties-water=universal solvento Solvent=liquid or gas in which small amounts of other

substances (solute) can be dissolvedo Solvent+solute=solutiono Respiratory gases and waste can dissolve in water

A. Water

o Mucus and saliva use water as their solvent

3. Chemical Reactivity-• Water=very important type of reaction• Water molecules are added to larger bonds to digest

food and break down biological molecules (hydrolysis reaction)

4. Cushioning-water forms a cushion around organs, such as the brain, to protect it from trauma

B. Salts

• Most plentiful salts contain calcium and phosphorus (found in bones and teeth)

• Dissociation: when salt dissolves in the body and separates in its ions

• Salt is vital to a body functioning• All salts are electrolytes-substances that

conduct and electric current in a solution

C. Acids and Bases

1. Characteristics of Acids:

• Sour taste, can dissolve metal

• Acid-a substance that can release hydrogen ions in detectable amounts

• Acids are proton donors

• Acids in the body: hydrochloric, acetic, carbonic

• Strong vs. weak acids

C. Acids and Bases

2. Characteristics of Bases:• Bitter taste, slippery• Proton accepters• Hydroxides are common inorganic bases• Any base containing the hydroxl ion is a strong

base• Bicarbonate ion (in blood) is weaker• When acids and bases mix, they form water and

salt• Neutralization reaction-when an acid and a base

react

C. Acids and Bases

3. PH: Acid-Base concentrations• The relative concentration of hydrogen ions in various body

fluids is measured in concentration units called PH units• PH scale: found in 1990 by Sorensen and is based on the the

# of protons in a solution expressed in terms of moles per liter• PH scale-014; 7= midpoint (neutral); 1-6 acids, 8-14 bases 1= stronger acid; 14=weaker base• Living cells are extraordinarily sensitive to even slight

changes in pH• Acid/base balance is regulated by the kidney, lungs, and a #

of chemicals called buffers (present in body fluids)

C. Acids and Bases

• Weak acids and weak bases are important to the body’s buffers systems which act to maintain pH stability

• Regulation of blood pH is critical• Normal blood pH ranges from 7.35-7.45;

small changes in this threaten death• When blood pH begins to dip into the acid

range, the amount of life-sustaining oxygen that the hemoglobin in blood can carry to body cells begins to fall rapidly to dangerously low levels

Acids and Bases

pH Scale