Vitamin K antagonists (VKA) are a group of substances that reduce blood clotting by reducing the action of vitamin K. They are used as anticoagulant medications in the prevention of thrombosis, and in pest control, as rodenticides. 1  1 Mechanism of action.  2 Coumarins (4-hydroxycoumarins)
Calculate the average atomic mass of oxygen. Solution: ((15.994915*99.757) + (16.999132*0.038) + (17.999160*0.205))/100 = 15.999405 . Using our equation for determining average atomic mass, we see that the average atomic mass for oxygen is 15.999405 amu. If we check the periodic table, we will see that our average atomic mass is the same as the atomic mass indicated on the element oxygen. Ã
Best Answer: Atomic oxygen is just one oxygen atom by itself, written as O. Molecular oxygen is a molecule of two oxygen atoms covalently bonded together, such that both atoms attain the stable octet configuration. It is written as O2. The molar mass simply means the mass of a substance in one mole (in grams). You can refer to your periodic table for the mass number. In this case, oxygen has a mass number of 16.0. Hence, atomic oxygen has a molar mass of 16.0g while molecular oxygen has a molar mass of 16.0*2 = 32.0g.