Unit 3 Quiz

Question 1

pH

Answer 1

Potential Hydrogen

Question 2

pH measures

Answer 2

the hydrogen ion concentration of a solution.

It tells whether the solution is an acid, a base, or is neutral

Question 3

Ion

Answer 3

an atom or molecule with an electrical charge

Question 4

pH Scale

Answer 4

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

Question 5

Between each consecutive number on the pH scale

Answer 5

it is 10x.
From 4 to 5 is 10x
From 7 to 8 is 100
From 2 to 5 is 1000
and so on

Question 6

pH Indicators

Answer 6

Anthocyanins
Chemical Reagents
pH Paper
pH Meter

Question 7

Anthocyanins

Answer 7

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

Question 8

The stronger the acid

Answer 8

the brighter the color

Question 9

Chemical Reagents

Answer 9

are chemicals used to determine pH of a solution

Question 10

pH Paper

Answer 10

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

Question 11

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

Answer 11

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

Question 12

Buffer

Answer 12

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

Question 13

How does a buffer work?

Answer 13

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+

Question 14

A solution has a low buffering capacity when

Answer 14

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

Question 15

A solution has a high buffering capacity when

Answer 15

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

Question 16

Buffering capacity is measured by

Answer 16

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

Question 17

Pure water has a

Answer 17

neutral pH. (pH=7)