Unit 3 Quiz Flashcards
pH
Potential Hydrogen
pH measures
the hydrogen ion concentration of a solution.
It tells whether the solution is an acid, a base, or is neutral
Ion
an atom or molecule with an electrical charge
pH Scale
I—————-I—————I
0 Acid 7 Base 14
H+ Neutral OH-
Between each consecutive number on the pH scale
it is 10x. From 4 to 5 is 10x From 7 to 8 is 100 From 2 to 5 is 1000 and so on
pH Indicators
Anthocyanins
Chemical Reagents
pH Paper
pH Meter
Anthocyanins
are plant pigments.
Acid- Red
Neutral- Blue
Base- Green/yellow
The stronger the acid
the brighter the color
Chemical Reagents
are chemicals used to determine pH of a solution
pH Paper
changes colors when you stick it in a solution, then you try and match the color to find out the pH
pH Meter and two things you have to do before you can use it
- take off the safety cap
- calibrate it
To use the pH meter you stick it in a solution and then read the pH off the display on the meter
Buffer
a solution that can resist drastic changes in pH when an acid or a base is added to it.
How does a buffer work?
Buffering is effected by the presence of a weak acid/weak base pair present in the solution. By weak acid/weak base, we are referring to a solution where there is not complete ionization of the acid when dissolved in water.
Buffers absorb or release excess H+
A solution has a low buffering capacity when
it is observed that pH changes fairly quickly when acid or base is added.
A solution has a high buffering capacity when
it is observed to resist changes in pH when an acid or base is added.
Buffering capacity is measured by
how much the solution resists change in its pH when acid or base is added to the solution.
Pure water has a
neutral pH. (pH=7)
