IPS Study Guide

4.9- Acidification Lab

Chapter 4, Section 9

-Sulfur dioxide and Hydrogen chloride create an acidic solution

Carbonic acid-> dissolved CO2
Sulfur Dioxide -> Acid Rain
- volcanoes
- industrial pollution
- acid rain kills forests, pollutes water, rivers, lakes, ponds etc.

Limestone -> porous, soft, sedimentary, holds a lot of water
aquifer-> water underneath land and also has limestone


BQ's p.91 (32-25)

32) Denver, CO; at the base of the Rocky Mountains

33) 2.5x10^-3/100=M/2000cm^3

.0025/100=M/2000

100M/100=5/5

M=.05/day 18.25/year

34) There is always a low level of toxic subs in public water; there would be no water if law was passed

35) Desert was once ocean; no rain to wash away/dissolve solids at surface

Limestone/Sinkholes

-Limestone: 1)porous (holds water) 2)soft 3) sedimentary 4)soluble in water (has carbonic acid)


-FL sinkholes occur because...

-Lots of limestone

-Water underground (aquifer)

-Once covered with ocean-> soft calcium deposits (dead animals)


Two Gasses Lab

-Magnesium Carbonate and Acid:

-CO2 down (dense gas sinks)

-Upright: filled with CO2, gas cannot escape, goes down

-Inverted: filled with air, gas escapes, goes down



-Magnesium and Acid:

-Hydrogen (H) goes up, light gas (rise)

-Upright: gas escapes, filled with air, goes up

-Inverted: gas cannot escape, filled with Hydrogen, goes up



-"Pop"

-Gas is ignited and rushes out of test tube; rubs against glass, causes friction (sound)

-Inverted: flammable gas escaping, goes down



Experimental Errors:

-Not waiting 30 sec.

-Unstopper before inverting

-Break surface water with test tube

-Do not collect full test tube of gas

-Air bubble in test tube

-Stoppers not tight

Not keeping test tubes vertical


*A lab group collects 400cm^3 of each gas. What would be the mass of each mass collected? Answer in decimal and scientific notation

-0.000089=M/400

0.0356; 2.6x10^2

-0.0018=M/400

M=0.72; 7.2x10^-1

Sulfuric Acid

-Discovered in 8th century by Alchemist-> Alchemy "Chemistry"


-Uses: 1)Lead Acid batteries (cars) 2)fertilizers 3)Steel industry-> prevent rust corrosion 4)Dried fruit production (hydrotropic)

FRAE p.92 36-45 (omit 44)

Acidification of Water Lab

Phenol Red:

-ph indicator

-red: basic

-clear: acidic


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 was more soluble in cup with straw

-because the carbonic acid lowers ph and dissolves calcium faster


Errors:

-not enough phenol red

-does not bubble water long enough

-2 cups do not have same amount of water

-lose water when using straw

-put CO2 into both cups

Ocean Acidification

-Ocean's ph has decreased 0.1

-about 25% drop in ph

-normal ocean ph: 8.0-8.4


-lower ph will cause shelled animals (shrimp, mollusks, etc.) to not be able to build a shell