Why do some green gram seeds float on water while some don't?
Which could mean one thing for sure . The density and weight of the grams which float is way too lower than the ones that sink. Which means, there is a possibility that it is hollow inside , because of some bug infestation or small worms/bugs gotten inside them, eaten them making it hollow. Else the natural weight if the gram is practically very low, and the growth is incomplete., Former being the most probable cause. If would examine the lot for any worms/bugs to ensure that's not the case. If proved clean, and the number of floating grams is much less, then I will just ignore and use. On the other hand, it there proves to be bugs/worms in the lot, the better option is just to discard them to be safe. Because, pulses and lentils infested with bugs mostly no longer taste the same. Thanks. Hope it helped.