More precisely it is the negative of the logarithm to base 10 of the activity of the hydrogen ion.[1] Solutions with a pH less than 7 are acidic and solutions with a pH greater than 7 are basic. Pure water is neutral, at pH 7, being neither an acid nor a base.
Report Abuse. 1  Ripe Plum. 2  This Site Might Help You. 3  A plum is ripe when its soft and a really dark purpleish color.  they should be a little soft and should have a smell (plum smell) strawberry Â· 9 years 1  ago. Smell it, squish it and last but not least bite 2  it! plump(really soft) and dark all 3  over. the color tells u everything u need to  know.
The plum is ripe and ready to eat when the flesh softens enough that gentle pressure from the thumb dents the skin. Unripe plums store best at temperatures between 31 and 32 F and at 90 to 95 percent humidity. Commercial growers are able to store plums for two to four weeks under these conditions before ripening.