Acids, Bases, and pH

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Acids, Bases, and pH
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Ph Scale measure of hydrogen ion concentration

• More acidic more hydrogen ions

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pH and the Environment
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Little known facts about acids and bases

• In many states the highway patrol carries
• two gallons of Coke in the trunk to remove blood
  from the highway after a car accident.
• Coke pH 3

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Little known facts about acids and bases

• To clean corrosion from car battery terminals
• Pour a can of Coca-Cola over the terminals to
  bubble away the corrosion.

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Little known facts about acids and bases

• One glass of water will shut down midnight hunger
  pangs for almost 100 of the dieters studied in a
  University of Washington study.
• Water pH 7

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What makes a solution acidic or basic?

• AcidsAcids are ionic compound that break
  apart in water to form a hydrogen ion (H).The
  strength of an acid is based on the concentration
  of H ions in the solution.
• The more H the stronger the acid.
• Example HCl (Hydrochloric acid) in water

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What makes a solution acidic or basic?

• Characteristics of AcidsAcids taste
  sourAcids react strongly with metals
• (Zn HCl)
• Strong Acids are dangerous and can burn your
  skinExamples of Acids1. Vinegar 2. Citrus
  Fruits 3. Stomach Acid (HCl)

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What makes a solution acidic or basic?

• II. BasesBases are ionic compounds that break
  apart to form a negatively charged hydroxide ion
  (OH-) in water.
• The strength of a base is determined by the
  concentration of Hydroxide ions (OH-).
• The greater the concentration of OH- ions the
  stronger the base.Example NaOH (Sodium
  Hydroxide-a strong base) in water
• Solutions containing bases are often called
  alkaline.

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What makes a solution acidic or basic?

• Characteristics of BasesBases taste
  bitterBases feel slipperyStrong bases are
  very dangerous and can burn your
  skinExamples1. lye (Sodium Hydroxide)2.
  Ammonia

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What makes a solution acidic or basic?

• pH Scale and IndicatorsThe strength of an acid
  or base in a solution is measured on a scale
  called a pH scale.

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• Any pH number greater than 7 is considered a base
  and any pH number less than 7 is considered an
  acid. 0 is the strongest acid and 14 is the
  strongest base

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What makes a solution acidic or basic?

• Indicators-- An indicator is a special type of
  compound that changes color as the pH of a
  solution changes, thus telling us the pH of the
  solution

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What makes a solution acidic or basic?

• Anthocyanins, are plant pigments that can be used
  a pH indicators because they change color in
  response to changes in ph.

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What makes a solution acidic or basic?
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What makes a solution acidic or basic?

• Buffer - an ionic compound that resists changes
  in its pH
• Buffering Capacity - The extent to which a buffer
  solution can absorb the added acid or base while
  changing little in pH.