Acid Rain

Acid RainA term first coined in 1856, it is used to describe how “acidic” soil may be

due to the result of pollution in the air mixed with precipitation.

Acid Rain"Acid rain" is a broad term referring to a

mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amounts of

nitric and sulfuric acids.

Acid RainSO2 – Sulfur Dioxide

NOx – Nitrogen Oxide

NH4 –

Ammonium

Hg - Mercury

Problems

Acid RainWATER: Acid rain causes acidification of lakes

and streams and contributes to the damage of trees at high elevations (for example, red spruce

trees above 2,000 feet) and many sensitive forest soils. In addition, acid rain accelerates the

decay of building materials.

Acid RainTREES/PLANTS: Acid rain does

not usually kill trees directly. Instead, it is more likely to weaken

trees by damaging their leaves, limiting the nutrients available to them, or exposing them to toxic

substances slowly released from the soil. Quite often, injury or death of trees is a result of these effects

of acid rain in combination with one or more additional threats.

PEOPLE: Many scientific studies have identified a

relationship between

elevated levels of acid rain and increased illness and premature

death from heart and lung

disorders, such as asthma and

bronchitis.

Acid Rain

Gargoyle damaged by acid rain

pH

pH ScaleScientists study pH (acid) in the soil and grade it on a scale from 0 – 14.

0 – 6.9 is acid

7 is neutral

7.9 – 14 is basic

What Can We Do?

Individuals and society as a whole can participate in various efforts to help reduce acid deposition:*Understand acid deposition’s causes and

effects *Clean up smokestacks and exhaust pipes *Use alternative energy sources *Restore a damaged environment *Look to the future *Take action as individuals

LABAcids and Bases

• Acids taste sour, are corrosive to metals, change litmus (a dye extracted from lichens) red, and become less acidic when mixed with bases.

• Bases feel slippery, change litmus blue, and become less basic when mixed with acids.

When they react, neutralization, water and salt are created

Effects on Environment

Acids are generally pure substances which contain hydrogen ions (H+) or cause them to be produced in solutions

~ acids are corrosive in nature and will be found in car batteries, foods we eat/drink, and in insect stings and venoms.

~ will dissolve plant roots and leaves if too much is found in the soil

Effects on Environment• Base is most commonly thought of as an aqueous

substance that can accept hydrogen ions (opposite of an acid)

~ the base, when mixed with an acid, produces a neutralization (putting baking soda on a bee sting takes the acids out of the sting itself and sooths the injury)

~ Environments with limestone and sea water are base-rich environments – changing its levels will change the organisms that live there.

[H+] pH Example

Acids

1 X 100 0 HCl

1 x 10-1 1 Stomach acid

1 x 10-2 2 Lemon juice

1 x 10-3 3 Vinegar

1 x 10-4 4 Soda

1 x 10-5 5 Rainwater

1 x 10-6 6 Milk

Neutral 1 x 10-7 7 Pure water

Bases

1 x 10-8 8 Egg whites

1 x 10-9 9 Baking soda

1 x 10-10 10 Tums® antacid

1 x 10-11 11 Ammonia

1 x 10-12 12 Mineral lime - Ca(OH)2

1 x 10-13 13 Drano®

1 x 10-14 14 NaOH