Question

solve it and send me please

Answer 1

If 99% is 20 the the total must be approximately 20 bt more then 20 and As we know that the mass of any element is somewhat more than the mass of its isotope which has highest concentration. So in this case X^20 has 99% of its abundance. Hence weight of X element shoulď be a little more greater than 20 as other isotopes has its abundance of 1%. Therefore after checking the options, we would find that its answer is 20.002
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