Basic Chemistry


Published on

  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Basic Chemistry

  1. 1. Basic Chemistry
  2. 3. Basic Chemistry <ul><li>Matter – anything that occupies space and has mass </li></ul><ul><li>Element – a substance that can’t be broken down to other substances </li></ul><ul><ul><li>The body is made mainly of O (oxygen), C (carbon), H (hydrogen), and N (nitrogen). </li></ul></ul><ul><ul><li>It also consists of trace elements , which are needed, but only in small quantities (Ca, calcium; P, phosphorous; K, potassium; and S, sulfur). </li></ul></ul>
  3. 5. Control Minus Nitrogen
  4. 6. Goiter – minus Iodine
  5. 7. The Atom The smallest unit of matter that still retains the properties of an element.
  6. 8. Structure of the Atom <ul><li>Has 3 basic particles: </li></ul><ul><ul><li>Proton – single unit of positive charge </li></ul></ul><ul><ul><li>Electron –single unit of negative charge </li></ul></ul><ul><ul><li>Neutron – no charge; neutral </li></ul></ul><ul><li>Nucleus – atom’s central core which contains the protons and neutrons </li></ul><ul><li>Electrons orbit around the nucleus. </li></ul>
  7. 10. Periodic Table <ul><li>Using the periodic table, we can determine what the actual structure of an atom of a certain element. </li></ul><ul><li>Atomic number – the number of protons in each atom of an element </li></ul><ul><li>Mass number – the sum of the number of protons and neutrons in an atom’s nucleus </li></ul><ul><li>Formula: Mass # - Atomic # = # Neutrons </li></ul>
  8. 13. Find the # of protons, neutrons, and electrons for each element.
  9. 14. Electron Arrangement <ul><li>Electrons determine how at atom will behave. </li></ul><ul><li>Electrons occur in energy levels, sometimes called electron shells or orbitals. </li></ul><ul><li>Depending on the atomic #, the atom can have 1, 2, 3, or more shells. </li></ul><ul><li>Electrons in the outer shell have the most energy. </li></ul>
  10. 15. Electron Arrangement (con’t) <ul><li>Each shell can hold a certain # of electrons. </li></ul><ul><li>Formula: 2(n 2 ) = # of electrons in the shell </li></ul><ul><li>The # of electrons in the outer shell determines the chemical properties of the atom. </li></ul><ul><li>Shells that aren’t completely full interact with other atoms. </li></ul>
  11. 17. Determine the # of protons, electrons, and neutrons for each. Then, draw the atom.
  12. 18. Ions <ul><li>An ion is an atom that has a positive or negative charge due to the loss or gain of electrons. </li></ul><ul><li>Gain electrons = negative charge </li></ul><ul><ul><li>C -2 – carbon atom with 2 extra electrons </li></ul></ul><ul><li>Lose electrons = positive charge </li></ul><ul><ul><li>C +2 – carbon atom with 2 less electrons </li></ul></ul>
  13. 19. Types of Ions <ul><li>Cations - have lost electrons (p+ > e-) giving them a positive charge. </li></ul><ul><li>Anions - have gained electrons (p+ < e-) giving them a negative charge. </li></ul>
  14. 20. Isotopes <ul><li>Isotopes have the same number of protons and electrons, but a difference in the number of neutrons. </li></ul><ul><li>Radioactive isotopes have decaying nuclei, which give off particles and energy. They are used in biological research and medicine as tracers. </li></ul>
  15. 25. Chemical Bonding <ul><li>Chemical Bond – an attraction between 2 atoms, resulting from a sharing of outer-shell electrons OR the presence of opposite charges on the atoms. </li></ul><ul><li>Types of bonds: </li></ul><ul><ul><li>Ionic </li></ul></ul><ul><ul><li>Covalent </li></ul></ul>
  16. 26. Ionic Bonding <ul><li>Ions have a positive or negative charge. </li></ul><ul><li>An ionic bond is the attraction between oppositely charged ions. </li></ul>
  17. 28. Covalent Bond <ul><li>Forms when 2 atoms share one or more pairs of outer-shell electrons. </li></ul><ul><li>The number of covalent bonds at atom can form is equal to the number of electrons needed to fill its outer shell. </li></ul>
  18. 29. Chemical Reaction <ul><li>A process leading to chemical changes in matter; involves the making and/or breaking of chemical bonds. </li></ul><ul><li>Chemical reactions cannot create or destroy matter, but only rearrange it. </li></ul><ul><li>Reactant – starting material </li></ul><ul><li>Product – ending material </li></ul>
  19. 30. 2H 2 + O 2  2H 2 O Product Reactants
  20. 31. Water <ul><li>Made of 2 hydrogen atoms and 1 oxygen atom joined by a covalent bond. </li></ul><ul><li>It is a polar molecule, having opposite charges on opposite ends. </li></ul><ul><li>This allows cohesion, which is the tendency of molecules to stick together via hydrogen bonds. </li></ul>
  21. 33. Solution <ul><li>A liquid consisting of a homogeneous mixture of two or more substances. </li></ul><ul><li>Parts of a solution: </li></ul><ul><ul><li>Solvent – dissolving agent </li></ul></ul><ul><ul><li>Solute – substance being dissolved </li></ul></ul><ul><li>Aqueous solution – water is the solvent </li></ul>
  22. 34. Acids and Bases <ul><li>Acid – chemical compound that donates H + to solutions </li></ul><ul><ul><li>Ex. HCl </li></ul></ul><ul><li>Base – chemical compound that donates OH - to solutions and accepts H + </li></ul><ul><ul><li>Ex. NaOH </li></ul></ul>
  23. 35. pH Scale <ul><li>Scale used to describe the acidity or basicity of a solution </li></ul><ul><ul><li>Ranges from 0 – 14 </li></ul></ul><ul><ul><ul><li>0 – most acidic </li></ul></ul></ul><ul><ul><ul><li>7 – neutral </li></ul></ul></ul><ul><ul><ul><li>14 – most basic </li></ul></ul></ul>
  24. 37. Buffers <ul><li>Substances that resist changes in pH by accepting H + when there are too many, or donating H + when there is not enough. </li></ul>