environmental chemistry c focus on soil lin wozniewksi lin [email protected]

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Environmental Environmental Chemistry C Chemistry C Focus on Soil Focus on Soil Lin Wozniewksi Lin Wozniewksi [email protected] [email protected]

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Environmental Environmental Chemistry CChemistry C

Focus on SoilFocus on Soil

Lin WozniewksiLin Wozniewksi

[email protected]@iun.edu

SafetySafety

Students must wear:Students must wear: Closed shoesClosed shoes Slacks or skirts that come to the anklesSlacks or skirts that come to the ankles Sleeved ShirtSleeved Shirt Lab coat or lab apronLab coat or lab apron Indirect vent or unvented chemical splash proof Indirect vent or unvented chemical splash proof

goggles. No impact glasses or visorgogs are goggles. No impact glasses or visorgogs are permittedpermitted

Students can bringStudents can bring

CalculatorCalculator 1 sheet of paper on which anything 1 sheet of paper on which anything

handwritten is acceptablehandwritten is acceptable A writing instrumentA writing instrument

Supervisors will provideSupervisors will provide

The instrumentsThe instruments The materials to testThe materials to test Any calibration curves necessaryAny calibration curves necessary Any other testing materials necessaryAny other testing materials necessary Instructions on how to use instrumentation or Instructions on how to use instrumentation or

test kits.test kits.

Main FocusMain FocusSoil NutrientsSoil NutrientspHpHFertilizersFertilizersEffects of soil Effects of soil

TemperatureTemperatureDifference Difference

between sand, between sand, silt, & claysilt, & clay

What plants needWhat plants needPorosity, water Porosity, water

retention, & retention, & permeabilitypermeability

ContaminantsContaminantsRemediationRemediation Impacts of over Impacts of over

fertilizationfertilization

Main Focus

Gas Spectrogram retention timesGas Spectrogram retention timesMass SpecMass SpecDilutions, unit conversions & Dilutions, unit conversions &

Stoichiometric calculations Stoichiometric calculations How to prepare students How to prepare students ResourcesResources

Soil NutrientsSoil Nutrients 3 3 Main classes of Main classes of

nutrientsnutrients Absolutely necessaryAbsolutely necessary

NitrogenNitrogen PhosphorousPhosphorous PotashPotash

VitalVital Calcium Calcium MagnesiumMagnesium SulfurSulfur

TraceTrace Iron, Manganese, Zinc, Iron, Manganese, Zinc,

Boron, Copper, Boron, Copper, MolybdenumMolybdenum

Chlorine, Silicon, Chlorine, Silicon, Nickel, CobaltNickel, Cobalt

Soil TestingSoil Testing

Test kits are available at local garden centers and Test kits are available at local garden centers and Sears costing from ~$3-5. Often enough material for Sears costing from ~$3-5. Often enough material for several tests are includedseveral tests are included

Numbers are not usually given, just very low, low, Numbers are not usually given, just very low, low, optimum, and above.optimum, and above.

Even professional soil testers will give not only the Even professional soil testers will give not only the numbers (which will vary from laboratory to numbers (which will vary from laboratory to laboratory and hence are unreliable) will also give laboratory and hence are unreliable) will also give the results in terms of very low, low, optimum, high.the results in terms of very low, low, optimum, high.

pHpH

Many plants need a slightly acidic soilMany plants need a slightly acidic soil The natural pH of most water is about 6 The natural pH of most water is about 6

because of the carbon dioxide dissolved in it.because of the carbon dioxide dissolved in it. Some flowers like hydrangeas have different Some flowers like hydrangeas have different

colored flowers in different pH soilscolored flowers in different pH soils Many plants produce natural indicators that Many plants produce natural indicators that

change colors in different pH’schange colors in different pH’s

Calcium and MagnesiumCalcium and Magnesium

Both Calcium and Magnesium are vital to Both Calcium and Magnesium are vital to proper plant growthproper plant growth

Neither are tested for in a standard NPK soil Neither are tested for in a standard NPK soil test kittest kit

Can be tested for by testing a digested sample Can be tested for by testing a digested sample

RemediationRemediation

To raise the pH of acidic soils (below pH 5.8), To raise the pH of acidic soils (below pH 5.8), add lime (limestone)add lime (limestone)

To lower the pH of basic soils (above pH 8.3) To lower the pH of basic soils (above pH 8.3) that do not contain free carbonate, add sulfur.that do not contain free carbonate, add sulfur.

Since limestone is a combination of calcium Since limestone is a combination of calcium and magnesium carbonate, it can be added to and magnesium carbonate, it can be added to increase the carbonate level if necessary.increase the carbonate level if necessary.

FertilizersFertilizers NPK Fertilizers are only concerned with the 3 NPK Fertilizers are only concerned with the 3

Absolutely Necessary ingredientsAbsolutely Necessary ingredients Nitrogen in the form of Ammonia (NHNitrogen in the form of Ammonia (NH33) and Nitrate ) and Nitrate

(NO(NO33--))

Phosphorous (Usually in the form PPhosphorous (Usually in the form P22OO55))

Potash (KPotash (K++) (Usually as K) (Usually as K22O)O)

The numbers on the bag tell the weights of each The numbers on the bag tell the weights of each ingredient, in that orderingredient, in that order

There are lots of different fertilizers for various There are lots of different fertilizers for various purposespurposes

FertilizersFertilizersMaterial N P2O5

(%)K2O

MgO S

Ammonium Nitrate 35 0 0 0 0

Ammonium Sulfate 21 0 0 0 24

Calcium Nitrate 15.5 0 0 0 0

Diammonium Phosphate 18 46 0 0 0

Monoammonium phosphate 11 52 0 0 0

Muriate of Potash 0 0 60 0 0

Potassium Nitrate 13.5 0 44 0 0

SKMG or SULPOMAG 0 0 22 18 22

Sulphate of Potash 0 0 50 0 18

Single Super Phosphate 0 22 0 0 14

Triple Super Phosphate 0 46 0 0 0

Urea 46 0 0 0 0

Effect of TemperatureEffect of Temperature Water has a very high specific heat because of Water has a very high specific heat because of

the hydrogen bondingthe hydrogen bonding This means it can store a lot of heat in the This means it can store a lot of heat in the

bondsbonds Moist soil will not warm up as fast as dry soilMoist soil will not warm up as fast as dry soil Dry soil will not cool down as fast as wet soilDry soil will not cool down as fast as wet soil Most plants prefer an optimal temperature for Most plants prefer an optimal temperature for

maximum growth-they will not grow properly maximum growth-they will not grow properly if too hot or too coldif too hot or too cold

What Plants NeedWhat Plants Need

The Nitrogen is used for green leavesThe Nitrogen is used for green leaves The Phosphorus is used for strength and the The Phosphorus is used for strength and the

root systemroot system The Potash is used for fruits.The Potash is used for fruits. Most plants need a neutral pH around 6-6.5Most plants need a neutral pH around 6-6.5 Plants need balanced nutrition and not just Plants need balanced nutrition and not just

NPK fertilizersNPK fertilizers

Fertilizer Good or BadFertilizer Good or Bad

A good fertilization plan can be more A good fertilization plan can be more beneficial for the environment than no beneficial for the environment than no fertilizationfertilization

A properly applied fertilization program will A properly applied fertilization program will promote plant growth which will prevent soil promote plant growth which will prevent soil erosionerosion

Proper fertilization means only applying what Proper fertilization means only applying what is necessary and not over applyingis necessary and not over applying

Pollutant or Contaminant?

It is a pollutant if it is supposed to be there, but the substance is present in higher quantity than it should be. Fertilizers, some ions, etc. Sometimes metals are thought of as contaminants, but

many soils contain arsenic and mercury naturally It is a contaminant if it is not supposed to be there

at all Plastics

PollutantsPollutants

Are metals pollutants or trace nutrients?Are metals pollutants or trace nutrients? It depends on the concentrationsIt depends on the concentrations Some copper, iron, etc. are necessary for plant Some copper, iron, etc. are necessary for plant

development.development. Plants take the metal ions up in their structure Plants take the metal ions up in their structure

and can be used to bio-remediate area, but then and can be used to bio-remediate area, but then the plants can not be used for food.the plants can not be used for food.

Remediation Remediation depends on source and size of problem Soil bacteria will digest many petroleum spills if the

spill is not large scale or buried deeply Underground storage tank leaks often have to be

dug out so bacteria can get to petroleum Clay will retain heavy metal contamination for long

periods Plants can be used to bio remediate soil Chemical reactions can be used for some

remediation Electrokinetic remediation using acetic acid has

achieved some success

Source of Pollutant/Contaminant Point Source – Used to be the biggest source

of pollution. This would be a single plant, a chemical spill, a single farmer, etc. Legislation has almost eliminated this type of pollution

Non Point Source – Now the biggest source of pollution. This would be petroleum products dripping off of vehicles, road salt, fertilizer from residential areas, etc. This is much harder to control

Mass Spec Most questions will either be

Match the picture Determine the weight of some part Determine the relative abundance of some part

Graphs have the mass of the components that the mass spectrometer

has broken the compound up into on the x-axis The relative abundance on the y-axis

GC Spectrograms Used to separate components of a mixture The further right a peak is, the longer it is

retained in the column This is usually because it has a higher affinity

for the stationary phase Or it has a lower affinity for the mobile phase The higher the peak is, the higher the

concentration of that particular component of the mixture

Preparation of Soil SamplesPreparation of Soil Samples Normally to test for metal ions, the soils must be Normally to test for metal ions, the soils must be

refluxed in concentrated nitric acid for about 24 refluxed in concentrated nitric acid for about 24 hours to remove the metals to be tested forhours to remove the metals to be tested for

Then the liquid is diluted.Then the liquid is diluted. Most of the ions are not colored and therefore need Most of the ions are not colored and therefore need

a reagent that when combined with the metal ions a reagent that when combined with the metal ions will be colored so the solution can be put in a will be colored so the solution can be put in a colorimeter.colorimeter.

Since this is time consuming and dangerous, it may Since this is time consuming and dangerous, it may be advantageous to “fake” the materials to be tested be advantageous to “fake” the materials to be tested for.for.

Preparation of Test MaterialsPreparation of Test Materials Food coloring makes an extremely good coloring Food coloring makes an extremely good coloring

agent.agent. If dilute enough, students would be hard pressed with the If dilute enough, students would be hard pressed with the

naked eye to tell the difference between a liter of water naked eye to tell the difference between a liter of water with a drop of red food coloring and an iron(III) solution with a drop of red food coloring and an iron(III) solution with phenanthrolene addedwith phenanthrolene added

Students would have a tough time telling with the naked Students would have a tough time telling with the naked eye the difference between a solution of copper(II) ion eye the difference between a solution of copper(II) ion and a dilute solution of water and blue food coloring. and a dilute solution of water and blue food coloring.

Black food coloring makes an extremely good base Black food coloring makes an extremely good base to hide other colors in.to hide other colors in.

Basic Types of Soil Sand – Largest particles – virtually no organic

material - try to form a 1” ball of moist soil in your hand & if it feels gritty & won’t stay together it is a sandy soil

Silt – Smaller particles, more organic material – considered most fertile - less gritty ball than sand, more gritty than clay, ball crumbles

Clay –Smallest particles - if the 1” ball feels smooth, plastic, requires lots of pressure to form, stays together well & forms ribbons between your fingers, it is clay soil

Other Soil types

Loam –made of some sand, silt, and clay - if the 1” ball feels partially smooth, partially gritty & forms a ball that easily crumbles it is loamy soil

Peat Soil – dead plant material – very acidic Chalky Soil – has a large number of stones and

is very alkaline

Porosity A measure of the void spaces in the soil as a

percentage of the soil Porosity = void volume/soil volume Sandy soil ~.43-.36 Clay soil ~ .58-.51 Seems counterintuitive Example

If 1 m3 of soil is actually .7 m3 of soil and .3 m3 of air and water

Porosity = .3 m3/1 m3 = .3 (sandy soil)

How to Measure Porosity

Easiest method is to measure a volume of the soil

Measure an amount of water Pour water into soil and collect that which runs

through Pour volume = Original volume of water –

volume collected

Permeability

The ability of the soil to transmit fluids In other words how quickly the water can flow

through the soil

1 meter of Will take _ to drain 1liter of water

Gravel 2 minutes

Sand 2 hours

Silt 200 days

Clay 200 years

How to Measure Permiability

Take a sample of soil .1 meter deep in a sieve or container with a drain

Take a volume of water Time how long it takes for the water to come

out the bottom of the container

Water Retention

Related to particle size, porosity, and permeability

Defined as water content as a function of matric pressure

A centrifuge is preferred to measure matric pressure

Often measured at the pore size in porosity measurements

Impacts of Over fertilization The main impact of over fertilization is the runoff

into streams and rivers The runoff into the streams and rivers causes

unnatural algae blooms Algae blooms take dissolved oxygen out of the

bodies of water When the dissolved oxygen is taken out of the

water, fish and macro invertebrates die Then you also have the problem of over production

of fertilizer at plants with the associated environmental costs

Calculations-Dilutions

Many fertilizers are liquids They are sold in concentrated forms and

require dilutions before use Students should be able to do calculations

involving dilutions

Calculations-Unit Conversions

Parts per notation is a measure of concentration Students need to be able to convert from one type

of concentration to another pph = parts per hundred = % ppm = parts per million = 1/1,000,000 = 1X10-6

Stoichiometry

Many contaminating heavy metals can be oxidized to remediate.

Oxides of most metals are insoluble in water and therefore removed from ecosystem

Oxidation can be by means of air injection or injection of strong oxidizer like ozone or permanganate

Some petroleum products are thermally burned

How To Prepare StudentsHow To Prepare Students

Practice Practice In teamsIn teamsWith soil test kitsWith soil test kitsWith instrumentsWith instrumentsWith calibration curvesWith calibration curvesDoing unit conversions, etcDoing unit conversions, etc

Make notesMake notes

How to Prepare StudentsHow to Prepare Students

Have students researchHave students research FertilizersFertilizers Plant nutrientsPlant nutrients Environmental effectsEnvironmental effects Trace nutrientsTrace nutrients ChromotographyChromotography

ResourcesResources Nutrient depleation Nutrient depleation

http://www.youngevity.ca/misc/mineral_depletion.php

Activity - Activity - http://www-tc.pbs.org/saf/1301/teaching/teach2.pdf

With Acid Rain With Acid Rain http://www.eurekalert.org/pub_releases/2004-03/uom-ars032604.php#

Tomato Plant nutrient requirements Tomato Plant nutrient requirements http://www.wikihow.com/Grow-a-Tomato-Plant

Reading Fertilizer Labels Reading Fertilizer Labels http://www.wikihow.com/Read-a-Fertilizer-Labelhttp://www.wikihow.com/Read-a-Fertilizer-Label

ResourcesResources Effects of nutrient deficiency on plants Effects of nutrient deficiency on plants

http://www.uga.edu/vegetable/home.htmlhttp://www.uga.edu/vegetable/home.html

Soil Testing http://www.lowes.com/lowes/lkn?Soil Testing http://www.lowes.com/lowes/lkn?action=howTo&p=LawnGarden/soiltest.htmlaction=howTo&p=LawnGarden/soiltest.html

Soil Test Kits http://www.shopping.com/xDN-Soil Test Kits http://www.shopping.com/xDN-garden--soil_testing_kits-price_range_10_20garden--soil_testing_kits-price_range_10_20

Fertilizer Numbers Fertilizer Numbers http://www.agroservicesinternational.com/index.htmhttp://www.agroservicesinternational.com/index.htmll

RescourcesRescources

Instrument labsInstrument labshttp://education.ti.com/educationportal/http://education.ti.com/educationportal/

activityexchange/activity_list.do?cid=usactivityexchange/activity_list.do?cid=usSource for all sorts of mass spectra & GCSource for all sorts of mass spectra & GChttp://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/http://riodb01.ibase.aist.go.jp/sdbs/cgi-bin/

cre_index.cgicre_index.cgihttp://webbook.nist.gov/chemistry/name-ser.htmlhttp://webbook.nist.gov/chemistry/name-ser.html Soil in GeneralSoil in Generalhttp://techalive.mtu.edu/meec/module06/Porosity.htmhttp://techalive.mtu.edu/meec/module06/Porosity.htm

Questions?Questions?

Thank YouThank You