1. Basic Chemistry

2. Element
Substances made entirely of one kind of atom: can’t be broken down into simpler substances (114 identified)

3. K:\Biochemistry\Tom Lehrer's The Elements_ A Flash animation by Mike Stanfill, Private Hand.mht

4. Atoms
Each element is made of atoms, which are the building blocks of matter
Atoms are the smallest part of an element that have the properties of that element

5. Most Common Elements in Living Things
Carbon
Hydrogen
Oxygen
Nitrogen
Smaller quantities of the elements:
sulfur, phosphorus, magnesium, iodine, iron, calcium, sodium, chlorine and potassium

6. Compounds
A substance composed of 2 or more elements that are chemically combined in definite proportions
Examples:
water (H2O)
carbon dioxide (CO2)
sodium chloride (NaCl)
glucose (C6H12O6)

7. Symbols Letters are used to represent elements
Examples :Na, O, Cl, C, H etc

8. Formulas Are used to represent compounds
Chemical Formulas: use letters to represent the elements and subscripts to show how many atoms of each element are present
ex: C6H12O6 glucose
H2O water
CO carbon dioxide

9. Formulas
Structural Formulas: show the number and kinds of atoms and how they are bonded together
Ex: glucose

10. Atomic Structure
Nucleus in the center, containing neutrons and protons and electrons travel around the nucleus in paths called orbits
Protons have a positive charge
Electrons have a negative charge
Neutrons have a neutral charge

11. Atomic number = the number of protons in the nucleus of an atom, the number identifies the element (also tells the number of electrons)
Atomic mass (mass number) = the number of protons + the number of neutrons

12. Isotopes
Atoms that differ from other atoms of the same element by the number of neutrons in the nucleus (have the same number of protons and electrons)
Ex: hydrogen has 3 isotopes – all have 1 proton but each has a different # of neutrons)

13. Covalent Bonds Elements combine by sharing electrons
Ex: water, chlorine, oxygen

14. Ionic Bonds
The force of attraction between 2 ions in a chemical compound
Elements combine by transferring electrons
EX: sodium chloride

15. Chemical Reactions
The process in which chemical bonds are broken and the atoms form new bonds, producing new substances
C6H12O6 + 6O2  6CO2 + 6H2O
Glucose + Oxygen  carbon dioxide + water

16. Reactants The substances that were present before a reaction started
C6H12O6 + 6O2  6CO2 + 6H2O
The reactants in this equation are glucose and oxygen

17. Products The new substances produced by the chemical reaction
C6H12O6 + 6O2  6CO2 + 6H2O
The products of this reaction are carbon dioxide and water

18. Acids and Bases
An acid is any compound that produces hydrogen ions in solution
Examples: HCl – hydrochloric acid

19. Acids and Bases
A base is a compound that produces hydroxide ions when dissolved in water
Ex: NaOH – sodium hydroxide

20. Neutralization Reactions
The reaction of an acid with a base to produce a neutral solution
A neutralization reaction produces water and a salt as products
Ex: HCl + NaOH  NaCl + H2O
Hydrochloric acid + sodium hydroxide  salt + water

21. Acids and Bases
Substances can be classified as acids or bases based on their pH.
Acids have a pH from 1 to 6
Bases have a pH from 8 to 14
A pH of 7 is neutral

22. Indicators
Indicators are substances that change color and identify a substance as an acid or a base
Ex: Litmus paper (red and blue)
Red in acid , blue in base
Phenolpthalein colorless to pink in a basic solution
Methyl Orange -yellow to red in acid