Basic Chemistry & Atomic Structure
Basic Chemistry and Atomic Structure
Page 2: Learning Objectives
Students should be able to:
Name the four essential and most abundant elements of life.
Describe atomic structure; identify charge and location of protons, neutrons, and electrons.
Apply principles of atomic number and mass number.
Describe isotopes and radioactive isotopes.
Draw electron distribution diagrams for elements in the first three rows of the periodic table.
Explain why atoms are reactive.
Page 3: Composition of Life
Organisms are composed of matter (anything that occupies space and has mass).
Matter is made up of elements, anything that takes up space and has mass.
Element is a pure substance that can’t be broken down (carbon, iron, oxygen)
Atom is basic unit of matter
Page 4: Elements in the Human Body
Table of Major Elements:
Oxygen (O): 65.0% - Essential
Carbon (C): 18.5% - Most abundant
Hydrogen (H): 9.5%
Nitrogen (N): 3.3%
Calcium (Ca): 1.5%
Phosphorus (P): 1.0%
Potassium (K): 0.4% (Trace)
Sulfur (S): 0.3% (Trace)
Additional trace elements: e.g., Iron (Fe), Iodine (I).
Page 5: Basic Structure of Atoms
Atoms consist of three types of particles:
Protons (+)
Neutrons (0)
Electrons (-)
Atomic structure:
Protons and neutrons make up the atomic nucleus.
Electrons are located in the electron shells (cloud).
Protons and neutrons have a mass of approximately 1 dalton; electrons have negligible mass.
Page 6: Atomic Number and Mass Number
Atomic Number (bottom): The number of protons; defines the element.
Mass Number (top): Total number of protons and neutrons.
Note: Atomic mass differs slightly due to isotopic variations.
Page 7: Periodic Table
The periodic table organizes elements based on atomic structure and properties.
Familiarize with symbols and atomic weights of elements like:
Hydrogen (H): 1.0079
Carbon (C): 12.011
Nitrogen (N): 14.007
Nomenclature of elements essential for understanding.
Page 8: Practice Questions
Identify elements:
An atom with 7 protons and 7 neutrons.
An atom with 8 protons and mass number of 16; calculate neutrons.
An atomic number of 14 and 16 neutrons; find mass number.
Page 9: Isotopes
Definition: variations of atoms of same element with a different number of neutrons and mass numbers
Examples include Carbon-12, Carbon-13, and Carbon-14.
Greek roots: "iso" means equal, "topos" means place.
Page 10: Radioactive Isotopes
Definition: Unstable isotopes that decay and release particles and energy. (finding an age/how long ago did it die etc)
Examples: 18F, 11C, 238U, Technetium-99m.
Applications in medicine as radiotracers or radiation therapy (e.g., PET scans).
Page 11: Electron Configuration
Electron Shells:
First shell: maximum 2 electrons.
Second shell and third shell: maximum of 8 electrons.
Layout of elements like Hydrogen (H) and Carbon (C).
Page 12: Orbitals
Orbital: 3D space where electrons are likely to be found; usually contains a maximum of 2 electrons.
Structure exemplifies how electrons occupy shells.
Page 13: Rules for Electron Distribution
Steps to draw electron distribution diagrams:
Draw the nucleus and number of protons.
Place unpaired electrons first, then pair.
Fill inner shells before outer shells.
Page 14: Practice Diagrams
Practice drawing electron distribution diagrams for elements:
Boron (B)
Chlorine (Cl)
Familiarize with the diagrams for various elements.
Page 15: Atomic Reactivity
Atoms with incomplete outer shells are reactive.
Valence Electrons: Electrons in the outermost shell.
Page 16: Filling Valence Shells
Atoms react by accepting, donating, or sharing electrons to achieve full valence shells.
Page 17: Chemical Bonds
Atoms form chemical bonds when they join together to create molecules and compounds.
Page 18: In-class Exercise
Experiment with combining hydrogen and oxygen to form water (H2O).
Page 19: Vocabulary Summary
Key terms to know:
Element
Proton
Electron
Neutron
Atomic number
Mass number
Isotope
Vocabulary: Radioactive isotope, electron shell, orbital, valence electron, valence shell, chemical bond.