What is acid rain and what causes it?
Substance
Coke
Tap water
Lemon juice
Baking soda
Vinegar
Dish soap
Milk
Drain cleaner
Estimated
pH
Actual pH
Acid, base, or neutral?
2,3
5,6,7
2
8
1,2
8
7,6
11,10
Strong acid
Neutral, weak acid
Strong acid
Weak base
Strong acid
Weak base
Neutral, weak acid
Strong base
Bromothymol blue turns yellow when acidic, blue when base or
neutral. Put 50 mL bromo blue in a beaker. Add 1 drop of acid and
stir.
3,6,8,2 Drops of acid to make bromothymol blue turn yellow
2,5
Drops of base to turn it back to blue
1. Which solution was stronger, the acid or the base? How do you
know?
• Base was stronger.
• Took fewer drops than acid to change color.
Drops of acid to make bromothymol blue turn yellow
Drops of base to turn it back to blue
2. What happens when you mix acids and bases together?
They neutralize each other, cancel each other out.
3. What are two environmental problems related to acidity?
What can we do to solve them?
• Acid rain, ocean acidification.
• Reduce burning of fossil fuels.
Acid Rain
16. How does acid rain form, and why is it a problem?
Smog from coal burning mixes with rain clouds, making rain acidic.
Acidity hurts plants and animals.