ph & acid rain. what is an acid? an acid is a substance which, when dissolved in water, releases...
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![Page 1: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/1.jpg)
pH & Acid Rain
![Page 2: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/2.jpg)
![Page 3: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/3.jpg)
What is an Acid?
• An acid is a substance which, when dissolved in water, releases protons. ([H+] ions)
• The amount of protons ([H+] ions) released is a measure of the strength of the acid.
• For example, HCl (hydrochloric acid) is a strong acid, because it dissociates completely in water, generating [H+] and [Cl-].
![Page 4: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/4.jpg)
What is a Base?
• A base is a substance, when dissolved in water, releases hydroxide ions. ([OH-])
• The amount of the OH- ions released measures the strength of the base.
• For example NaOH is a strong base because it dissociates completely in water, generating [Na+] and [OH-].
![Page 5: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/5.jpg)
![Page 6: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/6.jpg)
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• Most living cells have a very narrow range of tolerance for pH.
•Acids are represented with a pH of 0-6.
•Bases are represented with a pH of 8-14.
•Neutral substances have a pH of 7. • Each pH unit represents a factor of 10 difference in [H+].
The pH scale goes from 0 to 14—because [H+][OH-] = 10-14
pH
10-2
10-3
10-5
10-4
10-8
10-7
10-6
[H+] M
10-10
10-9
10-11
10-12
10-13
10-14
10-1
100 A strong acid
A strong base
SOURCE: http://en.wikipedia.org/wiki/Image:PH_scale.png#file
![Page 7: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/7.jpg)
![Page 8: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/8.jpg)
How Can You Actually Determine the pH of a Solution?
• Use a pH meter—read the number.
• Use pH paper.– Acids turn litmus paper red.– Bases turn litmus paper blue.
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![Page 9: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/9.jpg)
What is Acid Rain?
• Acid rain is rain that has been made acidic by certain pollutants in the air.
• Normal Rain = 5.6 pH• Acid Rain = >5.0 pH
![Page 10: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/10.jpg)
What causes Acid Rain?
• Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide (SO2)and nitrogen oxides (NO) are released into the air.
• These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.
![Page 11: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/11.jpg)
What causes Acid Rain?
• Human activities are the main cause of acid rain. – Power plants - sulfur dioxide and nitrogen oxides
when they burn fossil fuels, such as coal, to produce electricity.
– The exhaust from cars, trucks, and buses releases nitrogen oxides and sulfur dioxide into the air.
![Page 12: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/12.jpg)
![Page 13: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/13.jpg)
![Page 14: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/14.jpg)
Why is Acid Rain harmful?
• Can cause respiratory problems in humans.
![Page 15: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/15.jpg)
• Can harm forests by seeping into ground.
![Page 16: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/16.jpg)
• Can damage buildings and objects.
![Page 17: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/17.jpg)
• Can damage lake and river life.
![Page 18: PH & Acid Rain. What is an Acid? An acid is a substance which, when dissolved in water, releases protons. ([H + ] ions) The amount of protons ([H +](https://reader030.vdocument.in/reader030/viewer/2022012323/56649ec85503460f94bd592b/html5/thumbnails/18.jpg)
• http://www.epa.gov/acidrain/education/site_students/acid_anim.html
• http://www.epa.gov/acidrain/education/site_students/foodweb.html