Science Study Guide
Acidification and Two Gases quiz - Brian Anderson
4.9 Acid Rain
Limestone: soft, porus, holds water
water soluble --> carbonic acid
Sinkholes are common in Fl. because:
-lots of limestone underground
-was covered by ocean in past
Sulfuric Acid Notes
-discovered in 8th century by Alchemist --> Alchemy "Chemistry"
Uses:
-Lead acid batteries (cars)
-Fertilizers
-Steel industry --> prevents rust corrosion
-Dired fruit production (hydrotropic)
Two Gases Lab
In magnesium Carbonate and Acid test tube: CO2 - dense gas sinks
Upright test tube:
filled with CO2 - gas can't escape because CO2 sinks
Inverted test tube:
Gas can escape - test tube fills with air
In Magnesium and Acid test tube: Hydrogen - light gas rises
Upright test tube:
Gas escapes - test tube fills with air
Inverted test tube:
Gas can't escape - filled with Hydrogen
"Pop"
Gas is ignited and rushes out of test tube. Rubs against glass which causes friction (making a sound)
Flammable gas escapes downward
Errors
not waiting 30 seconds
unstopper before inverting
break surface water with 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
Notes
-phenol red changes color as you add CO2 into water-the CO2 turns to carbonic acid lowering the ph of the water
-calcium tablet is more soluble in cup with straw
-this is b/c the carbonic acid lowers ph and dissolves calcium faster
Errors
-not enough phenol red
-don't bubble water long enough
-2 cups don't have the same amount of water
Ocean Acidification
-about 25% drop in ph
-Lower ph will cause shelled animals (shrimp, mollusks, etc.) to not be able to build a shell