Quiz 4.9 - Acid Lab Study Guide
Study Guide
Basic Info
Carbonic acid --> dissolved CO2
Sulfur Dioxide --> "acid rain"
|--> volcanoes + industrial pollution + geysers
Acid rain kills forests + pollutes water (river, lake, pond)
Limestone/ Sinkholes
Limestone:
-porous (holds H2O)
-soft
-soluble in H2O (carbonic acid)
FL Sinkholes occur b/c:
- lots of limestone
- water underground (aquafer)
-once covered w/ocean--> soft calcium deposits (dead animals)
Sulfuric Acid
-Discovered in 8th century by alchemists --> alchemy "chemistry"
Uses
- lead acid batteries (cars)
- fertilizers
- steel industry --> prevents rust corrosion
- dried fruit production (hydrotropic)
Two Gases Post Lab
- Magnesium + acid: Hydrogen is a light gas and it rises
POP Sound
- gas is ignited and rushes out of test tube. Rubs against glass causes friction (sound)
Experimental Errors
- not waiting 30 sec --> gas has to leave one test tube
- unstopper before inverting
- break surface H2O w/test tube
- don't collect full test tube of gas
- air bubble in test tube
- stoppers not tight
- not keeping test tubes vertical
Acidification Post Lab
- The CO2 turns to carbonic acid lowering the pH of the H2O
- Calcium tablet is more soluble in cup w/straw
- B/c the carbonic acid lowers pH + dissolves calcium faster
Experimental Errors
- Don't bubble H2O long enough (not enough CO2)
- 2 cups don't have same amount of H2O
- Lose water when using straw
- Put CO2 into both cups