Acids and Bases

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Acids and Bases
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Acids
Have a sour taste. Vinegar is a solution of
acetic acid. Citrus fruits contain citric acid.
React with certain metals to produce hydrogen gas.
React with carbonates and bicarbonates to produce
carbon dioxide gas
Bases
Have a bitter taste.
Feel slippery. Many soaps contain bases.
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Some Properties of Acids

• Produce H (as H3O) ions in water (the
  hydronium ion is a hydrogen ion attached to a
  water molecule)
• React with bases to form a salt and water
  
• Corrode metals
• Electrolytes
• Taste sour
• pH is less than 7
• Turns blue litmus paper to red
• Blue to Red A-CID

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Some Properties of Bases

• Produce OH- (hydroxyl) ions in water
• Taste bitter, chalky
• Are electrolytes
• Feel soapy, slippery
• React with acids to form salts and water
• pH greater than 7
• Turns red litmus paper to blue
• Basic Blue

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The pH scale is a way of expressing the strength
of acids and bases. pH can be viewed as an
abbreviation for power of Hydrogen - or more
completely, power of the concentration of the
Hydrogen ion. 0 - 7 acid 7 neutral
7 14 base
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pH of Common Substances
pH paper will indicate the pH of a substance by
the color it changes in a solution
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Learning Check AB1

• Describe the solution in each of the following
  as 1) acid 2) base or 3)neutral.
• A. ___soda
• B. ___soap
• C. ___coffee
• D. ___ wine
• E. ___ water
• F. ___ grapefruit

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Solution AB1

• Describe each solution as
• 1) acid 2) base or 3) neutral.
• A. _1_ soda
• B. _2_ soap
• C. _1_ coffee
• D. _1_ wine
• E. _3_ water
• F. _1_ grapefruit

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Learning Check AB2

• Identify each as characteristic of an A) acid
  or B) base
• ____ 1. Sour taste
• ____ 2. Produces OH- in aqueous solutions
• ____ 3. Chalky taste
• ____ 4. Is an electrolyte
• ____ 5. Produces H in aqueous solutions

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Solution AB2

• Identify each as a characteristic of an A) acid
  or B) base
• _A_ 1. Sour taste
• _B_ 2. Produces OH- in aqueous solutions
• _B_ 3. Chalky taste
• A, B 4. Is an electrolyte
• _A_ 5. Produces H in aqueous solutions