Welcome to Dr. Kate Brilakis' Learning Portal
pH
pH test strips
adding an acid to a solution increases H+ concentration
adding a base to a solution decreases H+ concentration
what's an acid?
pH meter
Using moles offers a consistent method to convert
between atoms or molecules and grams
ex:
Carbon (C) has 12.0 grams per mole (that's the atomic mass)
Oxygen (O) has 16.0 grams per mole
One molecule of carbon dioxide contains 1 carbon atom and 2 oxygen atoms...
number of grams per mole CO2 = 12.01 + [2 x 16.00]
number of grams per mole CO2 = 12.01 + 32.00
number of grams per mole CO2 = 44.01 gram/mole
What is a mole?
A mole is just a unit of measurement...like saying a dozen of something.
Chemical reactions occur at levels where using grams often isn't practical, but using numbers of atoms/molecules/ions wouldn't work either. Moles, therefore, serve as a middle man, between teeny weeny numbers and huge numbers.
what does the pH number really mean?
One mole is Avogadro's number
of particles which = which is 6.02 × 10*23
A dozen flowers = 12 flowers
A mole of carbon atoms = 6.02x10*23 carbon atoms
A mole of cookies = 6.02x10*23 cookies
pH is the negative log of the Hydrogen ion concentration.
In short, to identify a solution's pH, look to the exponent of that solution's Hydrogen ion concentration expressed in Molarity (moles/l).
Above, the H+ concentration is 1 x 10-*5 M meaning the concentration is
.00001 M or 1/100000 M.
how will we measure pH?
a mole?
so what's a base?