What is the average atomic mass of the element? an element, x, has two isotopes, x-14 and x-15. use the data in the table to find the average atomic mass of element x. isotope atomic mass abundance (%) x-14 14.003 99.636 x-15 15.000 0.364 the average atomic mass of element x is blank amu.

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.