Calculate the average atomic mass of rubidium. rubidium has two isotopes, 85rb and 87rb. 85rb has an atomic mass of 84.912 amu and occurs at an abundance of 72.17%. 87rb has an atomic mass of 86.909 amu and occurs at an abundance of 27.83%. show your work.

The average atomic mass of rubidium is 85.466 amu.

For calculating the average atomic mass of the Rb, the atomic masses for both the isotopes are taken into consideration.

The has atomic mass = 84.912 amu

The abundance of = 72.17 %

The average atomic mass of = 84.912

= 61.28 amu

The has atomic mass = 86.909 amu

The abundance of = 27.83%

The average atomic mass of = 86.909

= 24.186 amu

The average atomic mass of Rb will be = +

= 61.28 + 24.186 amu

= 85.466 amu.

The average atomic mass of rubidium is 85.466 amu.

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a saline water is fed to a reverse osmosis unit at flow rate o rotameter connected to reject (retentate) line reads 8 installed in reject and permeate line reads 15.2 milli siemens/cm and 300 micro siemens/com respectively.