Answer:
Chlorine (35.44 amu)
Explanation:
An unknown element is found to have three naturally occurring isotopes with atomic masses of 34.9689 (76.000%), 36.9659 (23.988%) and 35.9683 (0.012%).
We need to find the mass of the unknown element. When abundances is given, then atomic mass is given by :
[tex]M=34.9689 (76.000\%)+36.9659 (23.988\%) +35.9683(0.012\%)\\\\=34.9689 (\dfrac{76}{100})+36.9659 (\dfrac{23.988}{100}) +35.9683(\dfrac{0.012}{100})\\\\=35.44\ \text{amu}[/tex]
So, the atomic mass of the unknown element is 35.44 amu and it is chlorine.
