THE ACID RAIN Environmental Engineer Group

INTRODUCTION

ACID DEPOSITION 1. Dry deposition - Acidic gases and particles 2. Wet deposition - Acidic rain, fog and snow

THE ACID RAIN What is Acid rain? - Acid rain is rain, snow or fog that is polluted by acid in the atmosphere and damages the environment. ACID RAIN DROP

Acid Rain (Acid Precipitation) Any precipitation carrying dissolved acids from natural or man made causes. Examples; a. CO2 dissolves in H2O > Creates carbonic acid (H2CO3) b. Sulfur dioxide (from internal combustion) mixes with H2O > Sulfuric Acid (H2SO4) c. Nitrogen oxides (from internal combustion) mixes with H2O > Nitric Acid (HNO3) * Acid precipitation may have a pH as low as 3. Very Acidic! * Acids in the air may be carried thousands of miles from their source, polluting soil & water in pristine areas!

DAMAGES THE ENVIRONMENT

pH

a number on a scale of 0 to 14 which shows how acid or alkaline a substance is Measure the amount of acid in a liquid – like water

The Water Molecule Formula of water = H 2 0 H = hydrogen 2 = 2 hydrogen atoms O = oxygen.

Pour acid into water give up H + to water = acid Pour base into water give up OH - to water = base

Ph SubstanceSodium Hydroxide LyeLime (Calcium hydroxide) AmmoniaMilk of Magnesia Baking Soda Human Blood Base Pure Water MilkTomatoWine & Bee AppleVinegarLemon Juice Battery Acid Hydrochloric Acid Neutral Acid

Ph SubstanceSodium Hydroxide LyeLime (Calcium hydroxide) AmmoniaMilk of Magnesia Baking Soda Human Blood Base Pure Water MilkTomatoWine & Bee AppleVinegarLemon Juice Battery Acid Hydrochloric Acid Neutral Acid

Normal rain = slightly acidic = 5.5 (carbon dioxide dissolves into it) In 2000, rain pH = 4.3 (in the US)

Sulphur dioxide (SO 2 )

cause by natural phenomena and anthropogenic activities is soluble in water can be oxidised within airborne water droplets producing sulphuric acid

Comes From combustion of fossil fuels oxidation of organic material in soils volcanic eruptions biomass burning

Reaction Sulphur dioxide is an acidic gas Easily be made by adding water SO 2 (g) SO 2 (aq) SO 2 (aq) + H 2 O (l) H 2 SO 3 (aq) weakly dibasic acid

Nitrogen Oxide ( NOx )

The Combustion Of Fuels Residential cars commercial furnaces Industrial electrical-utility boilers Engines other equipment

Canada’s largest contributor of NOx ( 1998 )

America’s largest contributor of NOx ( 1998 )

the NOx emissions amount ( 1998 )

Critical Load & Target Load Critical Load: a measure of how much pollution an environment can tolerate Target Load: the amount of pollution that is considered achievable and politically acceptable

The amount of wet sulphate deposition (kg/ha/yr)

Environmental Engineer History of Acid Rain Major problem area

History of Acid Rain 1.Originated during the 1730's 2.Discovered in the 1950's 3.Started being noticed in the 1960's － Germany － United Nations

Major problem area

Canada British Columbia United States Central Europe Asia

Reference Virtual Globe d06.html The acid rain report story2.html Living Landscapes ereandclimate/acidprecip.html#a