The graph shows how the pH value of soil in a farm changed over a period of time

The graph shows how the pH value of soil in a farm changed over a period of time

i) Describe how the pH of the soil can be determined
ii) State one factor that may have been responsible for the change in the soil pH in the time interval AB.

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i) Put soil in water in a beaker. To the mixture add a universal indicator and compare the colour change to the pH chart

OR

Add distilled water to the soil sample and stir. Add 2 drops of universal indicator to the
mixture and compare with the PH chart

ii) Addition of nitrogenous fertilizers which are acidic

OR

- Extensive use of acidic fertilizers
- Pollution by acid rain.

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johnmulu answered the question on April 21, 2017 at 12:44

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