Experiment #8 & #9

I did some testing after class and discovered that beakers 5-7 and 9-10 were a bit mixed up

Real pH (labelled pH)

0.9 (1)

2.1 (2)

3.4 (3)

4.2 (4)

4.6 (7)

5.4 (5)

6.7 (6)

7.8 (8)

10 (10)

12.1 (9)

So I re-ordered the test tubes to show lowest to highest pH and re-took the photos  - shown below.

HINT - When assessing a natural indicator you have to ask - does it have distinct colour changes at certain pH's? Does the one colour give a consistent pH (or consecutive range of pH's)? Are the colours easy to interpret?

Photos show pH:  0.9,  2.1,  3.4,  4.2,  4.6,  5.4,  6.7,  7.8,  10,  12.1

BEETROOT (oops - I forgot to switch the 9 & 10 - yellow should be pH 10)

BLUEBERRY

RED CABBAGE

STRAWBERRY

BROMOTHYMOL BLUE

LITMUS

METHYL ORANGE

PHENOLPHTHALEIN

UNIVERSAL INDICATOR