If you are asking about pregnancy, then in that case, this is also called Linea Nigra. One of the most common sign of pregnancy. It runs up the abdomen between the pubic area and bellybutton, or even higher. It is usually about .25-.5 inch wide, growing darker as the pregnancy advances.
You would still have 651 g of a certain compound but in different products, so the splitting of water via electrolysis you still have 2 Hydrogen and 1 Oxygen.
