The average atomic mass of copper is `63.5`. It exists as two isotopes which are `._(29)^(63)Cu and ._(29)^(65)Cu`. Calculate the percentage of each isotope present in it.

Explanation

Let the percentageof `overset(63)underset(29)Cu` isotope =x
The percentage of `overset(65)underset(29)Cu` isotope =100-x
From the above data the average atomic mass of Cu=`(63xxx)/(100)+(65xx(10-x))/(100)`
But the given average atomic mass of cu =63.5 `mu`
`therefore (63x xx)/(100)+(65xx(100-x))/(100)=63.5`
63x+6500-65x=6350
-2x=6350-6500=-150
2x=150
x=75 `mu`
Percentage of `overset(63)underset(29)Cu` isotipe = 75%
Percentage of `overset(65)underset(29)Cu`=25%