Lecture 6 - CHEMISTRY PDF

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CHEMISTRY...

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1. H3O is called the hydronium ion. Water molecules attach to hydronium ion and stabilize it. 2. Strong acids ionize completely, dissociate into separate ions, dominant species would be hydronium ion + non-metal ion. 3. Weak acids undergo incomplete ionization, dominant species would be the solute. 4. Polyprotic acids only lose their first hydrogen easily. 5. To predict the products of acid/base reaction 1. Determine which is an acid and which is a base. 2. Know that H2O is always a byproduct. 3. The metal from base bond with the non-metal from acid. 4. If there is also a precipitation reaction, consider that reaction separately by knowing the aqueous ions in each net ionic equation. 6. Writing Balanced Equation for Neutralization Reactions 7. Acid-Base Titration 1. Useful for figuring out the exact molarity of some unknown acid/base. 2. Procedure: 1. Identify the unknown solution as either a base or an acid 2. Add indicator that changes color when the equivalent point has been reached (pH = 7) 3. Slowly add the opposite of it (acid-base, base-acid) 4. Read the volume of your substance added and calculate the moles of that substance. Now you have the moles for both your substance and the unknown substance. 5. Use the molarity formula to compute molarity of unknown solution 8. Oxidation-Reduction Reactions (REDOX) 1. Most reactions used for energy production are redox reactions. 2. In human, the oxidation of sugars, fats, and proteins provides the energy necessary for life. 3. Combustion is another example. 4. In a REDOX reaction, one species lose electrons and another species accepts electrons. In another word, electrons move between atoms! 5. 6. OIL RIG (oxidation is lost, reduction is gain) 9. Oxidation Numbers (States) 1. A way of counting electrons, not real. 2. Oxidation number (states) represents the number of electrons required to produce the "effective charge" on a species. 3. 4. Elements with oxidation state of 0 are called "electrically neutral atoms" 5....