4.9- Acidification Lab Study Guide
Quiz Monday 3/16
Acid Rain & Global Warming (4.9 Note)
- Carbon Dioxide
-Sulfur Dioxide
- Hydrogen Chloride
- Carbon Dioxide dissolved in Water = CARBONIC ACID
- Sulfur Dioxide = acid rain
- Caused by: volcanoes, hot springs, industrial pollution
- Causes: dead forests, polluted water
Limestone & Sinkholes
Sinkholes occur b/c:
- Lots of limestone
- Water underground (aquifer)
- Once underwater -> soft calcium deposites (after evap.) from dead animals build up (sedimentary)
Snow melting picks up sediment/ mineral as it melts on mountain = large amounts of minerals (ex: calcium carbonate) at base of mountain ranges
Deserts have lots of mineral deposites (evaporated ocean once has all these minerals dissolved in it)
Sulfuric Acid
- Discovered in 8th century by alchemist
- Alchemy: trying to make gold out of cheaper materials
- "Chemist"
Uses:
- Lead acid batteries (cars)
- Fertilizers
- Steel industry -> prevents rust corrosion
- Dried fruit production (hydrotropic)
TWO GASES LAB
- dense gas
- Upright tube: gas can't escape (filled with carbon dioxide)
- Inverted: gas escapes (filled with air)
Magnesium and Acid: creates hydrogen
- flammable, light gas (ex: Hindenburg)
- Upright: gas escapes (filled with air)
- Inverted: Gas can't escape (filled with hydrogen)
"POP" = hydrogen is ignited and rushes out of tube
- rubs against glass -> creates friction = sound
Errors:
- Not waiting 30 sec.
- Unstopper before inverting
- Break surface of water with tube
- Don't collect full tube of gas
- Air bubble in tube
- Stoppers not tight
- Not keeps tubes vertical
ACIDIFICATION OF WATER LAB
- red = basic
- clear = acidic
Phenol red changes color as you add carbon dioxide into water
- Turns into carbonic acid, lowering pH of water
Calcium tablet is more soluble in cup w/straw b/c:
- carbonic acid lowers pH and dissolves calcium faster
Errors:
- Don't bubble water long enough
- 2 cups don't have same amt. of water
- Lose water when using straw
- Put carbon dioxide into both cups
Ocean Acidification
- Normal ocean pH is 8.1-8.4
- Ocean's pH has decreased 0.1 (about 25%)
- Lower ocean pH means sea animals with shells (made of calcium carbonate) can't make shell b/c:
- carbonic acid in water dissolves calcium carbonate