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Question
Under what soil conditions do you think a farmer would treat the soil of his fields with quicklime (calcium oxide), or slaked lime (calcium hydroxide) or chalk (calcium carbonate)?
Solution
Calcium oxide, calcium hydroxide and calcium carbonate are all bases (pH > 7), and hence, they must be used only in cases where the soil is too acidic (pH < 7). They help in neutralising the acidity of the soil and assist in bringing the pH closer to 7.
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