ACIDS and BASES
ACIDS Release Protons (H+)
Bases release hydroxide (OH-)
pH scale is a negative logarithmic scale (base of 10)
pH scale measures the amount of hydrogen in
moles/L
A mole is 6 x 10exp23 particles
pH of 5 then is 10-5 moles/L of H+
pH of 3 is 10-3
A pH of 7 is a neutral solution
A neutral solution contains an equal amount of H+
and OHAbove pH 7 the solution is basic
Below 7 the solution is acidic
A solution that has a pH of 3 is 100 times more
concentrated than a solution that has a pH of 5
Since …..10-3 / 10-5 = 100
pH scale is biologically important – your blood has a
pH between 7.3.5-7.45
Above (alkalosis) or below (acidosis) this value can
be fatal
The big idea here is most organisms are sensitive to
pH changes
A drop in pH in the oceans can lead to dissolving of
calcium carbonate (ie coral reefs)
Carbon dioxide reacts with water to form carbonic
acid
Sulfur dioxide reacts with water to form sulfuric
acid
Lakes of sulfuric acid near volcanoes can have pH of
0.5. How many times stronger is it relative to your
stomach? (pH2)
A neutralization reaction occurs between an acid
and a base.
Thought question …. Your stomach is acidic. Your
small intestine is basic. What type of chemical is
released to deal with the contents of the stomach
as they empty into the small intestine?
Base – Sodium bicarbonate
A neutralization reaction produces water plus at
least 1 other compound.
Ex. HCl + NaOH  H20 + NaCl
H2SO3 + Ca(OH)2  H20 + CaSO4
Practice
1. How many times more acidic is a pH 2 solution
relative to a pH6? pH 1.5 vs 5; pH 3.3 vs pH 6.6
2. Write the neutralization between ammonium
hydroxide and nitric acid; between potassium
hydroxide and hydrosulfuric acid.
ACIDS and BASES
ACIDS Release Protons (H+)
Bases release hydroxide (OH-)
pH scale is a negative logarithmic scale (base of 10)
pH scale measures the amount of hydrogen in
moles/L
A mole is 6 x 10exp23 particles
pH of 5 then is 10-5 moles/L of H+
pH of 3 is 10-3
A pH of 7 is a neutral solution
A neutral solution contains an equal amount of H+
and OHAbove pH 7 the solution is basic
Below 7 the solution is acidic
A solution that has a pH of 3 is 100 times more
concentrated than a solution that has a pH of 5
Since …..10-3 / 10-5 = 100
pH scale is biologically important – your blood has a
pH between 7.3.5-7.45
Above (alkalosis) or below (acidosis) this value can
be fatal
The big idea here is most organisms are sensitive to
pH changes
A drop in pH in the oceans can lead to dissolving of
calcium carbonate (ie coral reefs)
Carbon dioxide reacts with water to form carbonic
acid
Sulfur dioxide reacts with water to form sulfuric
acid
Lakes of sulfuric acid near volcanoes can have pH of
0.5. How many times stronger is it relative to your
stomach? (pH2)
A neutralization reaction occurs between an acid
and a base.
Thought question …. Your stomach is acidic. Your
small intestine is basic. What type of chemical is
released to deal with the contents of the stomach
as they empty into the small intestine?
Base – Sodium bicarbonate
A neutralization reaction produces water plus at
least 1 other compound.
Ex. HCl + NaOH  H20 + NaCl
H2SO3 + Ca(OH)2  H20 + CaSO4
Practice
1. How many times more acidic is a pH 2 solution
relative to a pH6? pH 1.5 vs 5; pH 3.3 vs pH 6.6
2. Write the neutralization between ammonium
hydroxide and nitric acid; between potassium
hydroxide and hydrosulfuric acid.