Anything that has mass and takes up

space

The food you eat is matter held together by chemical

energy

Atoms are composed of the following:

Protons - ________ charge

Electrons - ________ charge

Neutrons - ________ charge

+--o

“atomos” - indivisible

p+

n0

Electrons have virtually no mass. The

electron cloud is far more spread

out then nucleus.

Electrons are the part of the atoms involved

in chemical reactions.

electron

Elements are made of only 1 kind of atom

Elements cannot be broken down into smaller parts or another substance.

96% of living matter is made of C,H,O,N,

25 Elements Are ESSENTIAL to All Life

Most of an atom’s mass is contained in the nucleus.

Proton – a subatomic particle with a positive charge

Neutron – a subatomic particle with no charge

(electrically neutral)

It would take 3 million carbon atoms to stretch across the period at the end of a

sentence in your text book!!!!!!

A subatomic particle with a negative charge.

Electron’s have very little mass.

They move around the nucleus at a high rate of speed, but are held close by its attraction to protons in the nucleus.

Alternate forms of an atom

They have the same number of protons but differ in the

number of neutrons.

Atomic Mass = Protons + Neutrons

An isotope in which the nucleus decays giving off

radiation in the form of matter and energy.

Uses: “Biological Spies” – injected into cells and then as the isotope decays instruments

detect the radiation and follow the cells.

The number of protons found in a particular atom.

All atoms of the same element have the same

number of protons.

The # of protons determine the elements properties.

An atom is said to be electrically neutral if left alone.

The # of protons = The # of electrons

……………….however, the # of electrons doesn’t remain constant!

The structure of an atom will determine the chemical

properties of a particular substance.

An electron’s reactivity is dependent upon the

atom’s electrons in the highest energy level.

Atoms that naturally have full energy levels have the tendency to

NOT REACT!!!

Forms Water

Needed for Respiration

Released After Photosynthesis

Organic matter makes up all living

things

Carbon is found in all organic

matter

Hydrogen helps to

form water

Hydrogen is found in all organic

matter

Found in proteins

Found in DNA

Important in plant growth

These are the elements that make up less then .01% of your body.

They are however critical to the health of your body.

A healthy diet is critical to maintain proper trace elements levels.

Compound – 2 or more different elements that

are chemically combined

Compounds occur when one element interacts with another element.

What holds together elements in compounds?

Electrons are G, T, S!

They are given, taken, or shared by the elements in a compound.

They are also the part of the atom that takes part in chemical reactions

Chemical Bonds

Ionic bonds are bonds that occur when an atom transfers electrons to

another atom.

***Compounds formed by the attraction of ions***

Ex. NaCl Na+ + Cl-

A bond forms when Na loses an e- and Cl gains an e-

Atoms are usually neutral.

(# of protons = # of electrons)

Ions - electrically charged atoms

Positive Ion = an atom that loses an electron

Negative Ion = an atoms that gains an electron

Ionic Compounds are important to the human body.

*Na+ and K+ and Cl- help to move nerve impulses.

*Ca+ helps muscles to contract.

Covalent bonds occur when two atoms share electrons to form a bond.

Molecular compounds are compounds made of

molecules.

Molecule = a group of atoms held together by energy via covalent bonds

Tells you the # what kinds of atoms are in each molecule.

CaCl2 KCl

PbCl2 CH4

H2O2 NaCl

A molecule is a compound if it has more then one type of atom. Oxygen gas (O2) is a molecule but not a compound.

Water (H2O) is a molecule and can be a compound.

During a chemical reaction, bonds are

breaking and atoms are rearranging to form new

bonds.

Molecules become rearranged into different molecules. A chemical reaction can release or

absorb energy.

6CO2 + 6H2O C6H12O6 + 6O2

Sun’s Energy

Elements properties

change after a chemical reaction!

All living things depend on water.

Our bodies consist of 60-70% water!

One water molecule = 2 H atoms and 1 O atoms

Because of the 8 protons that exist in oxygen versus the 1 proton that exists in hydrogen,

oxygen pulls the electrons toward it much more strongly when the bonds in the molecule form!!

A molecule in which opposite ends have opposite

electric charges.

The attraction of the hydrogen atoms of one molecule and the negative atom of

another water molecule.

There is no transfer of electrons, so the bond isn’t

as strong as an ionic bond.

The attraction that occurs between unlike molecules.

The tendency of molecules of the same kind to stick

to one another.

Help to transport water from roots to the leaves of trees.

Ex. Cohesion – the surface tension on water allows insects to “skate”

across water.

Because of the hydrogen bonding, water has the

ability to resist temperature change.

The total amount of energy associated with the random

movement of atoms and molecules in a sample of matter.

The measure of average energy of random motion

of particles in a substance.

Importance of Temperature Moderation

Water takes longer to heat because of the energy it takes to

break those hydrogen bonds.

Ex. Oceans moderate surrounding lands.

Long lasting hydrogen bonds in the ice spread

out the water molecules

making it less dense then the

liquid form.

The bottoms of lakes and ponds freeze last. This keeps the nutrient rich muds open and the ice on top insulated the

water below.

Solution – a uniform mixture of 2 or more substance

Solute – the substance that is dissolved

Solvent – the substance that does the dissolving and is present in a great amount

Aqueous Solution – a solution in which water is the solvent

In aqueous solutions, a small amount of the H2O molecules break apart and H+ and OH-

ions are formed.

In order for the life processes in living systems to work

properly the number of OH-

and H+ ions must balance one another out.

An acid is a compound that donates additional H+ ions

in solution.

A compound that removes H+ ions from an aqueous solution.

Ex. Ammonia

Substances that cause solutions to resist changes in pH.

.

Ex. Blood’s pH = 7.4. If something acidic is introduced into the

bloodstream, a buffer will be present to take up the extra H+ ions

Anything that brings about change.

Energy can hold matter together or break it apart

Cooking – breaks the bonds of food

Matter and Energy

Examples:

Atoms

Living Things

Rocks

Soil

Air

Examples:

Sunlight

Electricity

Heat

Chemical energy

Found in Bones and

Teeth

Helps to Control

Stomach Acid

Found in DNA

Helps to pass along nerve

impulses

Found in proteins such as hair, skin, and muscles

Sodium is needed for

nerve impulses

Needed for passing nerve

impulses

Important in photosynthesis and

is found in chlorophyll.

99% of all living matter consists of the following elements:

C

H

O

N

P

S

Examples of Compounds

H2O = ___ H atoms and ___ O atom

CO2 = ___ C atom and ___ O atoms

O2 = ___ atoms

C6H12O6 = ___ C atoms, ___ H atoms and ___ O atoms

Mixture – a combination of substances in which

individual substances retain their properties

Ex. Salt and sugar, oxygen and carbon dioxide

Solution – two or more substances evenly mixed, one substance is dissolved in another

Suspension – a liquid or gas has another substance evenly

spread in itEx.

Blood and plasma, oil and water

They ALWAYS contain C and H and are associated with LIVING things or ONCE

living things

The 4 class of organic compounds include the following:

Fat and Lipids

Carbohydrates

Nucleic Acids

Proteins

Subunit: C, H, and O

Uses/Roles: sugars, starches and cellulose. They supply energy for the cells processes, from plant structure (cell wall), and are used for short-term energy storage

Subunit: C, O, H, and P

Uses/Roles: Fats, oil, waxes, and cholesterol. Contain large amounts of long term storable energy

Subunit: C, O, H, N, and S

Uses/Roles: Muscles, skin, hair, and enzymes. They

regulate cell processes, help to

jump start cell activities. Help to build cell structure.

Subunit: C, O, H, N and P

Uses/Roles: Found in DNA and RNA. Carry hereditary information and is used to make proteins

“Not of Life”

The most important Inorganic compound to

life is --- ???

Water is vital to all life.

50 - 60% of human body mass is due to water.

We can live weeks without food, but only days without water.

Water is a good insulator and it helps to maintain cell temperature.

The fact that ice floats helps to save many water organisms during cold winters.

Calcium Phosphate - adds strength to bones

Hydrochloric Acid - breaks down food in the stomach

Sodium Bicarbonate - helps digestion to occur

Salts - send messages along nerve cells