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
1 Mole = 6.02 x 1023 1 mole of atoms = 6.022 x 1023 atoms 1 mole of molecules = 6.022 x 1023 molecules Molar Mass: the mass (in grams) of one mole a particular substance There is a unique relationship between molar mass and atomic weight: Oxygenâs atomic weight is 16.00 amu. 1 mole of oxygen is 6.02 x 1023 atoms of oxygen 1 amu = 1.661 x 10-24g What is the molar mass (g/mole) of oxygen? 16.00 amu/oxygen atom x 1.661 x 10-24g/amu = 2.657 x 10-24 g/atom x 6.02 x 1023 atoms/mole =16.00 g/mole Molar mass (in grams) is always equal to the atomic weight of the atom! Molar mass (in grams) is always equal to the atomic weight of the atom! Examples: Atomic weight of carbon is 12.01amu Molar mass of carbon is 12.01 g/mol Atomic weight of helium is 4.00 amu Molar mass of helium is 4.00 g/mol Mole (mol): The number of particles (atoms or molecules) in a sample of element or compound with a mass in grams equal to the