Thread: Soil pH colour meanings.

The information below is used for the next three questions
Indicator paper used to test the pH of some soils had these colours.
pH Colour
1 Crimson
3 Pale red
5 Orange
7 Yellow
9 Pale green
10 Green
12 Turquoise
14 Blue

I know when you are measuring liquid that yellow is for acid, but what would the colour yellow indicate for a soil pH?

Originally Posted by Sazza

The information below is used for the next three questions
Indicator paper used to test the pH of some soils had these colours.
pH Colour
1 Crimson
3 Pale red
5 Orange
7 Yellow
9 Pale green
10 Green
12 Turquoise
14 Blue

I know when you are measuring liquid that yellow is for acid, but what would the colour yellow indicate for a soil pH?

Umm, according to your table, it would be pH 7, which is neutral.

what exactly are you asking?

I have to find out, what pH yellow indicates.

Originally Posted by Sazza

I have to find out, what pH yellow indicates.

which is what i don't get. you have the answers in the table you provided, just look it up. where you see yellow in the table, the pH beside it is 7, so pH 7 is what you are looking for. 7 is the pH for neutral compounds, so a color of yellow indicates that the soil is neutral

Originally Posted by Sazza

The information below is used for the next three questions
Indicator paper used to test the pH of some soils had these colours.
pH Colour
1 Crimson
3 Pale red
5 Orange
7 Yellow
9 Pale green
10 Green
12 Turquoise
14 Blue

I know when you are measuring liquid that yellow is for acid, but what would the colour yellow indicate for a soil pH?

pH 7, do you know what pH 7 signifies?

RonL

would the colour turquoise mean strong base?

Originally Posted by Sazza

would the colour turquoise mean strong base?

the lower the pH the more acidic it is, the higher the pH, the more basic it is. a pH of 7 indicates it is neutral

for turquoise we have a pH of 12, that is close to 14, so yes, i'd say we have a relatively strong base

for acids: 0 < pH < 7
for bases: 7 < pH <or= 14
for nuetral substances: pH = 7


there are some substances with pH greater than 14, but these are VERY rare, so most textbooks don't even consider them. as far as you are concerned, the highest pH possible is 14. the closer we are to 14 the stronger the base, the closer we are to 0, the stronger the acid, and nuetral is 7