html5-img
1 / 12

Chemical Symbols and Formulas

Chemical Symbols and Formulas. Chapter 2.7. Chemical Symbols. All elements in the Periodic Table have symbols that are recognized world wide . It does not matter which country you are in or the language you speak.

isleen
Download Presentation

Chemical Symbols and Formulas

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chemical Symbols and Formulas Chapter 2.7

  2. Chemical Symbols • All elements in the Periodic Table have symbols that are recognized world wide. • It does not matter which country you are in or the language you speak. • Example: The element Iron is always identified by “Fe” and Oxygen is “O”. • The names are not always the same but the symbols are. “Fe” is iron in Canada, fer in France and fier in Romania.

  3. Chemical Symbols A Chemical symbol is an abbreviation of a name of an element. Capital letter if only one letter. Only first letter capital if more than one letter

  4. Sodium comes from the word sodanum, a headache remedy, and it’s symbol (Na) comes from the Latin word Natrium.

  5. Chemical Formulas A chemical formula is the combination of symbols that represent a particular compound. The chemical formula indicates which elements are present in the compound and in what proportions. Ex. 1: Water molecule H2O: 2 atoms of hydrogen, 1 atom of oxygen Ex. 2: Iron Oxide molecule Fe2O3: 2 atoms of iron, 3 atom of oxygen

  6. Chemical Formulas - Examples • Calcium Carbonate (chalk) – CaCO3 • Sodium Chloride (salt) – NaCl • Acetysalicylic acid (aspirin) – C9H4O8 • Acetic acid (vinegar) – C2H4O2

  7. Chemical Formulas • NOTES: - Each symbol in a formula represents an element. - If only one atom of an element is present in the compound, no subscript is used. - If more than one atom of an element is used, then the symbol is followed by a number indicating how many atoms are used. This is called the subscript.

  8. Homework • Do Questions #1–5 on Page 59 • You may use your Periodic Table. • Make sure that for each question you write out that question first then you write your answer and then continue on to the next question and so on until completed.

  9. 1 atom of sodium 2 atoms of hydrogen (in a hydrogen molecule) 3 atoms of magnesium 2 atoms of phosphorus 8 atoms of oxygen 13 total atoms 3 carbon atoms

  10. Tomorrow Go over counting atoms worksheet Pass in Homework Chapter 2 quiz

More Related