Range of an indicator Flashcards
1
Q
Define the range of an indicator
A
The range of an indicator is the pH interval over which there is a clear change of colour for that indicator
2
Q
What is the approx. range of methyl orange?
A
3-5
3
Q
What is the approx range of litmus?
A
5-8
4
Q
What is the approx range of phenolphthalein?
A
8-10
5
Q
What is the acid colour (lower pH) of methyl orange?
A
red
6
Q
What is the acid colour (lower pH) of litmus?
A
red
7
Q
What is the acid colour (lower pH) of phenolphthalein?
A
colourless
8
Q
What is the base colour (higher pH) of methyl orange?
A
yellow
9
Q
What is the base colour (higher pH) of litmus?
A
blue
10
Q
What is the base colour (higher pH) of phenolphthalein?
A
pink
11
Q
What is universal indicator?
A
It is a mixture of indicators that gives a gradual change in colour over the entire range of the pH scale
