1. How do acids and bases interact with water?
Unit 5 Lesson 2 Acids, Bases, and Salts
How do acids and bases interact with water?
Water is made up of molecules of H2O. In any given sample of water, a small number of these molecules break apart to form hydronium ions (H3O+) and hydroxide ions (OH–).
An acid increases the number of positively charged H3O+ ions when it dissolves in water.
Lemon juice and vinegar both contain acid.
A base increases the number of negatively charged OH– ions when it dissolves in water.
Shampoo and window cleaner both contain bases.
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2. What is the difference between strong and weak acids and bases?
Unit 5 Lesson 2 Acids, Bases, and Salts
What is the difference between strong and weak acids and bases?
The strength of an acid or a base depends upon how many ions it releases into solution.
The strength of an acid or a base is not the same as its concentration. Dilute hydrochloric acid is still strong and can damage your skin, but concentrated citric acid does not harm your skin.
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3. What is the difference between strong and weak acids and bases?
Unit 5 Lesson 2 Acids, Bases, and Salts
What is the difference between strong and weak acids and bases?
In water, all of the molecules of a strong acid break apart completely, forming many H3O+ ions. All of the molecules of a strong base also break apart completely in water to form OH– ions.
Weak acids and bases do not break apart completely into ions. Only a few molecules form ions in water. Therefore, few hydronium ions or hydroxide ions are produced.
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4. What is the difference between strong and weak acids and bases?
Unit 5 Lesson 2 Acids, Bases, and Salts
What is the difference between strong and weak acids and bases?
How do strong acids and bases behave differently than weak acids and bases?
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5. What are the physical properties of acids?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are the physical properties of acids?
Acids taste sour. However, you should never use taste, touch, or smell to identify an unknown chemical. Some acids can damage body tissue. Most strong acids are poisonous.
When a strong acid is dissolved in water, it breaks apart and forms ions in solution. The ions make it possible for the solution to conduct an electric current.
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6. What are some chemical properties of acids?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are some chemical properties of acids?
Acids are corrosive. They can react with and destroy body tissue, clothing, and other things. Acids react violently with many metals.
Acids react with certain compounds called acid-base indicators. They cause the indicators to change color.
For example, litmus paper is a type of indicator. Blue litmus paper turns red in the presence of an acid.
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7. What are the physical properties of bases?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are the physical properties of bases?
Bases taste bitter. However, you should never use taste, touch, or smell to identify a base because many bases can cause burns.
Bases feel slippery. If your hands feel slippery while working with a base during a lab activity, immediately rinse your hands with water and tell an adult.
Like acids, solutions of bases conduct an electric current.
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8. What are some chemical properties of bases?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are some chemical properties of bases?
Bases are caustic. This property means that they can burn or corrode other substances.
Bases also change the color of acid-base indicators. Most indicators turn a different color in the presence of a base than they do in the presence of an acid.
For example, a base causes red litmus paper to turn blue.
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9. Shift into Neutral What is a neutralization reaction?
Unit 5 Lesson 2 Acids, Bases, and Salts
Shift into Neutral
What is a neutralization reaction?
A neutralization reaction is the reaction between an acid and a base in a water solution.
Two products of a neutralization reaction are water and a salt. Water molecules form when the hydrogen ions from the acid combine with the hydroxide ions from the base to make H2O.
A salt is an ionic compound that forms from the negative ion of the acid and the positive ion of the base.
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10. What are some examples of salts?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are some examples of salts?
The identity of the salt that forms in a neutralization reaction depends on the identities of the acid and base.
Salts have many uses in industry and in homes.
Sodium chloride is used to make baking soda as well as to season your food.
Sodium nitrate is a salt that preserves food.
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11. What are some examples of salts?
Unit 5 Lesson 2 Acids, Bases, and Salts
What are some examples of salts?
Calcium sulfate is used to make plasterboard, which is an important component in the construction of homes and buildings.
Calcium chloride is used to help keep ice from forming on roads and sidewalks in winter.
Calcium sulfate can be compressed into colored sticks of chalk used by artists.
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