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Chemistry, Part IHuman Anatomy and Physiology IOklahoma City Community College
Dennis Anderson
I. Matter and EnergyI. Matter and Energy
Slide 2.1Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• A. Matter – anything that occupies space and has mass (weight)
• B. Energy – the ability to do work
• 1. Chemical
• 2. Electrical
• 3.Mechanical
• 4.Radiant
Matter• Anything that takes up space and has mass
Elements
•Carbon (C)•Nitrogen (N)•Oxygen (O)•Hydrogen (H)
One Kind of MatterThe Fundamental units of matter
96% of the body is made from four elements
CompoundTwo or more elements combined together
•Carbon Dioxide•Sodium Chloride•Water
Atom
Minute particles that make up matter
Atomic Model
Proton
Neutron
Electron
Atomic StructureAtomic Structure
Slide 2.3Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Nucleus
• Protons (p+)
• Neutrons (n0)
• Outside of nucleus
• Electrons (e-)
Figure 2.1
Subatomic Particles
ChargeAtomicMass Unit
Proton Positive One
Neutron Neutral One
Electron Negative Near Zero
Atomic Number
• Hydrogen = 1• Carbon = 6• Oxygen = 8
Number of Protons
Protons = Electrons
Protons Electrons
Hydrogen 1 1
Carbon 6 6
Oxygen 8 8
Atomic Mass Number
Number of Protons and Neutrons
Hydrogen
• Atomic Number = 1• Atomic Mass Number = 1
Hydrogen Atom
First Energy LevelTwo Electrons Maximum
First Energy Level
Second Energy LevelEight Maximum
Second Energy Level
Third Energy LevelStable with Eight Electrons
Third EnergyLevel
Inert ElementsInert Elements
Slide 2.11Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Have complete valence shells and are stable
• Rule of 8s• Shell 1 has 2
electrons
• Shell 2 has 8 electrons
• 10 = 2 + 8
• Shell 3 has 18 electrons
• 18 = 2 + 8 + 8Figure 2.4a
Reactive ElementsReactive Elements
Slide 2.12Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
• Valence shells are not full and are unstable
• Tend to gain, lose, or share electrons
• Allows for bond formation, which produces stable valence
Figure 2.4b
Carbon• Atomic Number = 6• Atomic Mass Number = 12
Carbon Atom
6+ 60
Oxygen• Atomic Number = 8• Atomic Mass Number = 16
Oxygen Atom
8+ 80
Isotope
An atom of an element with a different number of neutrons than other atoms of the same element
Isotopes of Carbon
• Carbon 12 6 Neutrons• Carbon 13 7 Neutrons• Carbon 14 8 Neutrons• Carbon 15 9 Neutrons
Each Carbon has 6 protons
Atomic WeightAverage of the mass numbers of all
the isotopes of an element
Atomic Weight of Carbon = 12.01
Average Mass Numbers of Carbon 12,13,14 and 15
Radioactive Isotopes• Break down at a constant rate
–Half Life
Uses for Isotopes• Carbon 14 for dating the age of
skeletons• PET scan• Iodine isotope for thyroid studies• Cobalt isotope for cancer treatment
Sodium• Atomic Number = 11• Atomic Mass Number = 23
Sodium Atom
11+ 120
Chlorine• Atomic Number = 17• Atomic Mass Number = 35
Chlorine Atom
17+ 180
17+ 180
11+ 120
Sodium Ion Na+
Lost an Electron
11+ 120
Chloride Ion Cl-
17+ 180
Gained an Electron
Ion
An Atom or Molecule With a Charge
Formed by
-Gaining electrons
-Losing electrons
Ionic Bond
Cl-Na+
Chemical bond formed by the attraction of opposite charges
Chemical Bond
Force that holds atoms together in a molecule
Anion: Ion with a - ChargeCation: Ion with a + Charge
• Regulate water balance• Regulate acid-base balance• Form essential minerals
MoleculeTwo or More Atoms (Ions) Joined
Together
Cl-Na+
Sodium Chloride
Hydrogen Atoms
Electrons Shared
Covalent BondFormed by Sharing Electrons
Covalent Bond
H H
Four Covalent Bonds in Carbon
Structural Formula
HC
H
HH
Carbon Chain
C
H
HH C
H
HC
H
HC
H
HC
H
HC
H
HH
Water Molecule
+ +
Some Hydrogens Leave
+ +
Electron Stays with Water
+ +
Electron
+ +
Hydroxide Ion
Hydrogen Ion
Water
HOH
H+ OH-
Water
The number of
Equals the number of
H+
OH-
AcidChemical That Releases Excess Hydrogen Ions
HCl Cl-+H+
Base
OH-+Na+
Chemical That Releases Excess Hydroxide Ions
NaOH
pH Scale
01 2 3
78654
1411109 1312
OH-
H+
01 2 3
78654
1411109 1312
Hydrogen Ions =Hydroxide Ions
01 2 3
78654
1411109 1312
BaseAcid
01 2 3
78654
1411109 1312
Stomach Skin Blood
End of Part I