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.
Shell color is not necessarily a sign of maturity or ripeness. A pineapple can be ripe when it is practically all green outside. The plantation calls it âgreen-shell ripe.â Shell color of ripe fruit are divided into seven groups or levels ranging from No. 0, all green, to No. 6, all yellow. A pineapple will not ripen any further â get any sweeter â after picking. It is sugar that makes pineapple sweet after ripe. The sugar comes from the conversion of starch reserves in the stump at the time of ripening. Fresh pineapples from Hawaii are picked at maximum ripeness for delivery to U.S. markets.