Unit 3 Quiz Flashcards Preview

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Flashcards in Unit 3 Quiz Deck (17):
1

pH

Potential Hydrogen

2

pH measures

the hydrogen ion concentration of a solution.
It tells whether the solution is an acid, a base, or is neutral

3

Ion

an atom or molecule with an electrical charge

4

pH Scale

I----------------I---------------I
0 Acid 7 Base 14
H+ Neutral OH-

5

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

6

pH Indicators

Anthocyanins
Chemical Reagents
pH Paper
pH Meter

7

Anthocyanins

are plant pigments.
Acid- Red
Neutral- Blue
Base- Green/yellow

8

The stronger the acid

the brighter the color

9

Chemical Reagents

are chemicals used to determine pH of a solution

10

pH Paper

changes colors when you stick it in a solution, then you try and match the color to find out the pH

11

pH Meter and two things you have to do before you can use it

1. take off the safety cap
2. calibrate it

To use the pH meter you stick it in a solution and then read the pH off the display on the meter

12

Buffer

a solution that can resist drastic changes in pH when an acid or a base is added to it.

13

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+

14

A solution has a low buffering capacity when

it is observed that pH changes fairly quickly when acid or base is added.

15

A solution has a high buffering capacity when

it is observed to resist changes in pH when an acid or base is added.

16

Buffering capacity is measured by

how much the solution resists change in its pH when acid or base is added to the solution.

17

Pure water has a

neutral pH. (pH=7)