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.
Plum Trees With Large Fruit. Japanese plum trees (P. salicina) and Mexican plum trees (P. mexicana) produce large, edible plums that can be up to 3 inches in diameter. Both species grow to a height and width of about 25 feet and produce white spring flowers. Japanese plum tree fruit can be green, purple, red or yellow.