Lecture 20 Soil Acidity

Lecture 20 Soil Acidity - Soil Acidity and pH Acid Any...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Soil Acidity and pH Soil Acidity and pH Acid Acid Any substance which increases the Hydrogen ion concentration in solution. H + Hydrogen Ions and Organic Matter Hydrogen Ions and Organic Matter 0 7 14 Acidic basic High H+ concentration Low H+ concentration Inhibits dissociation of acidic functional groups Increases dissociation of acidic functional groups Low charge on Organic Colloids High charge on Organic Colloids COOH COO - + H +
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 Sources of Hydrogen Ions CO 2 from microbial respiration/atmosphere CO 2 dissolved in water produces carbonic acid H 2 CO 3 Acid functional groups on organic matter COOH COO - + H + Plant root exudation (release) of H + Acids in rainfall Gaseous nitrogen and sulfur oxides make acid rain Hydrolysis of aluminum can produce acids What are the acids in soils? Two Ions considered Acidic in Soils H + Aluminum Remember that aluminum is a common constituent of silicate clays Aluminum participates in “hydrolysis” reactions with water. Both are cationic
Background image of page 2
3 Hydrolysis of Water (ionization of water) H 2 O OH - + H + H + is the acid OH - is the base In pure water, the amounts of each are equal
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 10

Lecture 20 Soil Acidity - Soil Acidity and pH Acid Any...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online