Quiz 4.9

Acidification and Two Gases Labs

Gases Dissolved in Our Atmosphere

  • carbon dioxide, sulfur dioxide, and hydrogen chloride all create an acidic solution
  • carbonic acid -----> dissolved carbon dioxide
  • sulfur dioxide -----> "acid rain"

-volcanoes -kill forests

-industrial pollution -pollute water (rivers, lakes, ponds)

Sinkholes/Limestone

Limestone:

  • soft and porous (holds water)
  • water soluble -----> carbonic acid

Sinkholes:

  • common in Florida because:

-lots of limestone

-was once covered by ocean

Sulfuric Acid

  • discovered in the 8th century by alchemists -----> Alchemy -----> "chemistry"

Sulfur Acid:

  • uses:

-lead acid batteries (cars)

-fertilizers

-steel industry -----> prevents rust corrosion

-dried fruit production (hydrotropic)

Two Gases

Magnesium Carbonate and Acid:

  • Carbon dioxide sinks (dense)
  • the upright test tube is filled with CO2 and the gas can't escape
  • the inverted test tube is filled with air and the CO2 escapes

Magnesium and Acid:

  • Hydrogen rises (light)
  • the upright test tube is filled with air because the hydrogen escapes
  • the inverted test tube is filled with hydrogen because the gas can't escape

"Pop":

  • gas is ignited and rushes out of the test tube
  • gas rubs against glass and causes friction (sound)
  • the flammable gas is escaping

Phenol Red

  • ph indicator

-red: basic

-clear: acidic

Acidification of Water

  • 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 the straw

-because the carbonic acid lowers ph and dissolves calcium faster

Ocean Acidification

  • ocean's ph has decreased 0.1

-about 25% drop in ph

  • lower ph will cause shelled animals (shrimp, mollusks, etc.) to not be able to produce shells