Answer:
This element is Rubidium (Rb) and has an average atomic mass of 85.468 u
Explanation:
The average mass of an element is calculated by taking the average of the atomic masses of its stable isotopes.
The enitre atomic mass = 100 % or 1
⇒ this consists of X-85 with 72.17 % abundance with atomic massof 84.9118 g/mol
72.17 % = 0.7217
⇒ this consists of X-87 with 27.83 % abundance with atomic mass of 86.9092 g/mol
27.83 % = 0.2783
To calculate the mass of this isotope we use the following:
0.7271 * 84.9118 + 0.2783 * 86.9092 =85.468 g/mol
This element is Rubidium(Rb) and has an average atomic mass of 85.468 u
0.843 moles would be the answer
The element name is: Antimony
The chemical symbol: Sb
Atomic Mass: 121.75
Atomic Number: 51
Protons and neutrons.
Note: They probably are ABOUT the same mass. Don't think they are exactly the same.
Hope this helps!
Pure substances are further broken down into elements and compounds. Mixture are physically combined structures that can be separated into their original components. A chemical substance is composed of one type of atom or molecule.