1. Acids & Bases Adapted by: Mrs. Dube

2. What is Litmus?
An indicator used to determine whether a substance is an acid or base
Often prepared on paper slips
Acids – turn litmus paper red
Bases – turn litmus paper blue

3. What is an acid?
An acid is a solution that has an excess of hydrogen, H+, ions that it is free to donate
The more H + ions, the more acidic the solution

4. Properties of an Acid Taste sour
Produce a burning or prickling feeling on skin
Conduct Electricity
Corrosive, which means they break down certain substances
Some acids react strongly with metals producing hydrogen gas
Picture from BBC Revision Bites

5. Uses of Acids Acetic Acid = Vinegar
Citric Acid = lemons, limes, & oranges
In many sour candies such as lemonhead & sour patch.
Ascorbic acid = Vitamin C which your body needs to function.
Sulfuric acid is used in the production of fertilizers, steel, paints, and plastics.
Car batteries

6. Quick Quiz
How do you determine whether a solution is an acid or a base?
What happens to litmus paper when an acid is applied to the paper?

7. What is a Base?
A base is a solution that has an excess of hydroxide ions, (OH-) ions free to accept hydrogen H+ ions
Bases are substances that can accept hydrogen ions

8. Properties of a Base Feel slippery or soapy Taste bitter Corrosive
Strong bases can burn the skin
Can conduct electricity
Do not react with metals

9. Uses of Bases
Bases give soaps, ammonia, and many other cleaning products some of their useful properties.
The OH- ions interact strongly with certain substances, such as dirt and grease.
Chalk and oven cleaner are examples of familiar products that contain bases.
Your blood is a basic solution.

10. Quick Quiz What are some characteristic properties of an acid?
What are some characteristic properties of a base?

11. pH Scale pH is a measure of how acidic or basic a solution is.
The pH scale ranges from 0 to 14.
Acidic solutions have pH values below 7
A solution with a pH of 0 is very acidic.
A solution with a pH of 7 is neutral.
Pure water has a pH of 7.
Basic solutions have pH values above 7.

12. Quick Quiz Where are the strong acids found on the pH scale?
Where are the strong bases found on the pH scale?
How does the concentration of hydrogen ions change?
What is the pH of a neutral solution? A strong acid? A strong base?

13. Acid – Base Reactions
A reaction between an acid and a base is called neutralization
Products of a neutralization reaction are a salt and water

14. Acid – Base Reactions
Each salt listed in this table can be formed by the reaction between an acid and a base.

15. What are the products of an acid-base reaction?
Quick Quiz
What are the products of an acid-base reaction?