Anew element -- quickly named swiforskium by the scientific community -- is discovered. this element is found to have two isotopes. 86.4% of all swidorskium atoms are swidorskium-428 and 13.6% are swidorskium-433. what is the atomic mass of this element? show your work.

The average  atomic mass of this element is 428.68 .

Explanation:

Average atomic mass =

Atomic mass of Swidorskium-428 = 428

Abundance of Swidorskium-428 = 86.4%=0.864

Atomic mass of Swidorskium-433. = 433

Abundance of Swidorskium-433 = 13.6= 0.136

The atomic mass of the element is

= (atomic mass of Swidorskium-428 )(abundance) + (atomic mass of Swidorskium-433)(abundance)

The atomic mass of Swidorskium = (428)(0.864)+(433)(0.136) = 428.68

its volumetric flask