Acids and Bases

1
Acids and Bases

• Consumer chemistry

2
General formulas of acids and bases

• Acids generally begin with H or end in COOH
• Examples HCl hydrochloric acid
• CH3COOH ethanoic acid
• Bases generally begin with a metal element
  (located on the left side of the periodic table)
  and end in OH. A very common base that is an
  exception is NH3, which is ammonia
• Examples KOH potassium hydroxide
• Mg(OH)2 magnesium hydroxide

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Properties of acids

• Conductors in aqueous solutions
• Taste sour (but never taste anything in the lab!)
• Neutralize bases
• Have a pH less than 7, the lower the pH, the
  stronger the acid
• Form H ions in solution
• React with metals
• Common indicators colorless in phenopthalein,
  red in litmus

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Properties of bases

• Conductors in aqueous solution
• Taste bitter
• Neutralize acids
• Have a pH above 7, the further above 7, the
  stronger the base
• Form OH- ions in solution
• Do not react with metals
• Common indicators Pink in phenolpthalein, blue
  in litmus
• Feels slippery

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pH scale

• The pH measures the potential of hydrogen
• The pH scale ranges from approximately 0-14
• Every aqueous solution has both hydrogen and
  hydroxide ions, since water, H2O or (HOH),
  dissociates into H and OH-
• Acids have more H, bases have more OH- ions,
  which can be confusing, since acids have lower pH
  values
• Think of it alphabetically, a before b

pH 7 neutral
acid
base
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Acid, base, or salt?

• _____ NaOH
• _____ NaCl
• _____ HCl
• _____ C2H5COOH
• _____ LiOH
• _____ Al(OH)3
• _____ H2SO4
• _____ MgF

• _____ pH 5
• _____ pH 10
• _____ pH 7
• _____ litmus blue
• _____ litmus red
• ____reacts w/metal
• _____ pH 14
• _____ NH3

Base
acid
Base
salt
salt
acid
Base
acid
Base
acid
Base
acid
Base
acid
Base
salt
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Common acids

lemons
vinegar
Orange juice
soda
aspirin
Car battery
milk
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Common bases
Drain cleaner
antacids
ammonia
eggs
soap
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Neutralization reactions

• General formula
• acid base ? salt water
• Ex HCl NaOH ? NaCl H2O

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Titration formula

• MaVa MbVb
• (concentration of acid)(volume of acid)
  (concentration of base)(volume of base)
• M the concentration (molarity)
• V volume
• You must have 3 out of the 4 values in order to
  solve for the fourth

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Titration simulation

• http//lrs.ed.uiuc.edu/students/mihyewon/chemlab_e
  xperiment.html
• http//science.csustan.edu/chem/titrate/titrate1b.
  swf