Physical Science Ch' 25 Acids, Bases and Salts

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Physical Science Ch. 25Acids, Bases and
Salts Compare and contrast acids and bases and
identify the characteristics they have. Determine
the meaning of pH Determine what a salt is and
how salt forms.
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25.1 Acids and Bases What comes to mind when you
hear the word acid? Acid- a substance that
produces hydrogen ions (H) in a water
solution -contains at least one hydrogen atom
that can be removed when the acid is dissolved in
water, forming hydronium ions (H3O)
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• Properties of Acids
• Taste Sour
• Corrosive
• -to skin and tissue
• -react with some metals

3) React with indicator - -an organic compound
that changes color in acid and bases -example-lit
mus paper changes to red
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• Common Acids
• In Foods
• -citric acid in fruits
• -lactic in yogurt and buttermilk
• -acetic acid (vinegar) in pickled foods

• 2) Stomach
• hydrochloric acid to digest food

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3) Industry -sulfuric acid - batteries and
fertilizers -phosphoric acid - detergents,
fertilizers, soft drinks -nitric acid-fertilizers
and explosives -hydrochloric acid- clean steel
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• Base - a substance that forms hydroxide ions
  (OH-) in a water solution
• -also accepts hydronium ions from acids
• Properties of Bases-
• Crystalline solids - in pure, undissolved state
• Feel Slippery - in a solution
• Have a bitter taste
• Corrosive - strong bases
• Indicators - changes color
• -litmus paper changes to blue

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• Common bases
• cleaning products - ammonia
• -medications - milk of magnesia
• -fabrics -
• -deodorants

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Solutions of Acids and Bases -Acids compounds can
be ionized in water to form hydronium ions -Bases
compounds can form hydroxide ions in
solution -Both solutions are electric conductors
to some extent. Pg. 771, 1-5