The average atomic mass of two isotopes with mass numbers A and A + 2 is A + 0.25. Calculate the percentage abundance of the isotopes. Share with your friends Share 0 Geetha answered this Average atomic mass = x1M1 + x2M2x1 + x2Where x1 and x2 are the % abundance. M1 and M2 are the molar massx1 + x2 = 100 %x2 = 100 -x1Average atomic mass = x1M1 + x2M2x1 + x2 A+0.25 = x1 × A + (100 -x1) (A+2)100100 A + 25 = Ax1 + 100 A +200 - Ax1 - 2 x12x1 = 200 - 25 = 175x1 = 1752 = 87.5 %x2 = 100 -x1 = 100 - 87.5 = 12.5 % 0 View Full Answer
