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Well, that's limelight. What exactly was it? Well it was the burning of calcium oxide in a very intense flame. And when did the job of a limelighter begin? Oh, famously, the first recorded instance in
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pH - a measure of how acid or alkali a solution is. As the pH gets lower, the solution is more acid. At a pH of 7 the solution is neither acid nor alkali. pH is the inverse of the logarithm of the con
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