1. HOW CHEMISTRY IS CRUCIAL TO LIFE
To understand how chemistry is crucial to life, is to understand…
Atoms
Molecules
Bonding
Compounds

2. All living things are made of the same basic building blocks.
Chemistry
All living things are made of the same basic building blocks.
Atom: The smallest building blocks of matter. *They cannot be divided into smaller substances by ordinary (natural) processes.
Roughly 100 different kinds of atoms

3. Protons (positive [+] charge) Neutrons (no[0] charge) 1 H
Parts of the Atom
Nucleus: small central part of the atom that contains both protons and neutrons.
Sub Atomic Particles
Protons (positive [+] charge)
Neutrons (no[0] charge)
Electrons: (negative [-] charge) Negatively charged particles that orbit the outside of the nucleus
Atoms: in their normal state are electrically neutral (Same number of protons in the nucleus as electrons orbiting the outside

4. …ATOMS MOST FAMOUS ATOM TO A BIOLOGIST IS CARBON!
* To be defined later
MOST FAMOUS ATOM TO A BIOLOGIST IS CARBON!
Carbon is found in many different *compounds. It is in the food you eat, the clothes you wear, the cosmetics you use and the gasoline that fuels your car
Carbon is the sixth most abundant element in the universe
In addition, carbon is a very special element because it plays a dominant role in the chemistry of life. Why, because it has incredible *bonding capabilities

5. Atomic Number:
Is the number of protons in the nucleus (If the atom is in its normal state it also represents the number of electrons that orbit the outside) 1+ 8+

6. Atomic Mass The sum of the protons and neutrons in the nucleus.
Why don’t we count electrons?

7. Energy Levels 1st level can hold 2 electrons
2nd level can hold 8 electrons
3rd level can hold 8 electrons
If an atom has a filled outer most energy level the it is said to be a stable atom and will not form bonds with other atoms.
Ex) Noble gases (He, Ne, Ar, Kr, etc.)

8. If the outer most energy level of an atom is not filled then it is said to be unstable and it will form bonds with other unstable atoms to become stable
For example, Covalent or Ionic Bonds

9. Isotopes
The same type of atoms that have different numbers of neutrons
Varieties of atoms that are structurally the same but have a different number of neutrons.
*Same Atomic Number but Different Atomic Mass
ex) Oxygen 16(16O) Atomic # = 8, Mass # = 16 (8 neutrons)
Oxygen 17(17O) Atomic # = 8, Mass # = 17 (9 neutrons)
Oxygen 18(18O) Atomic # = 8, Mass # = 18 (10 neutrons)
What is a radioactive isotope?
It is an atom that has an unstable nucleus and it emits charged particles and transforms the atom to an atom of another element. Carbon 14(14C) Nitrogen 14(14N)

10. Elements Element: Substances that are made up of only on kind of atom.
Ex) A chunk of Au (Gold) or Ag (Silver)

11. ELEMENTS

12. …ELEMENTS The periodic table lists all known elements
They are classified based on their atomic number, a.k.a. number of protons
An element is an atom (one type of)
The element hydrogen is made of hydrogen atoms
The element carbon is made of carbon atoms

13. Compounds
Compound: Two or more atoms are bonded together. (Definite Proportions)
Ex) Water (H2O) or Carbon Dioxide (CO2)

14. Covalent Bonds
Form between the same or different types of atoms to form a molecule.
Two or more unstable atoms Sharing of Electrons to form a stable molecule.
Become stable by filling the outermost energy level
(H2O)

15. MOLECULE A group of atoms held together by a covalent bond
Remember me from Earth Science SiO44-

16. Diatomic Molecules Atoms that react with like atoms
Hydrogen Gas
Oxygen Gas
Nitrogen Gas
Most gases react this way

17. ION
An atom that has lost or gained a(n) electron(s). Giving it a charge other than neutral
Memorable examples…
Ca2+
Na+
Cl-

18. Ionic Bonds
Gaining or Losing an electron to fill the outermost energy level. Results in stable atoms that are now charged ions. The charged ion will form an electrical attraction (Ionic Bond) between oppositely charged ions
Yields + -

19. Ionic Bonds
Opposites attract to form compounds
ex) magnets + -

20. Chemical Formulas Atoms combined in definite proportions. ex) Water
2 hydrogen and 1 oxygen atoms
Glucose
6 carbons, 12 hydrogen, and 6 oxygen atoms
*Each Atom/Element is represented by its chemical symbol
(H2O)
(C6H12O6)

21. Structural Formula
Shows the number and types of atoms as well as how each atom is bonded together
Covalent bonds are represented by lines between atoms
One line indicates the sharing of one pair of electrons, 2 lines indicates the sharing of 2 pairs of electrons, etc.

22. Chemical Reactions
All compounds are made of a combination of atoms bonded to one another
When bonds between atoms are broken, different substances are formed “chemical reaction”
Reactants: substances before the reaction takes place
Products: new substance yielded after the reaction

23. Cell Respiration and Photosynthesis
C6H12O6 + 6O2 6 CO2 + 6 H20 + Energy
C6H12O6 + 6O2
6 CO2 + 6 H20 + Energy