Answer to Question #109172 in General Chemistry for Anastasia

Question

Gallium has two isotopes, one isotope is 69
Ga and has a relative abundance of 60.50% .
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The relative atomic mass of gallium is 69.70. what is the relative atomic mass for the other isotope.

Answer 1

Relative atomic mass = (( M1*A1)+(M2*A2))/100

where M1 and M2 are the atomic mass of isotope 1 & 2 respectively and A1 and A2 are the abundance of isotope 1 and 2 respectively.

According to the question

69.70 = ((69*60.50)+(M2* 39.50))/100

M2 = 70.77

Atomic mass of other isotope is 70.77