Question

on chemical scale, the relative mass of the isotopic mixture of x atoms (x^20,x^21,x^22) is approximately equal to:(x^20 has 99 percent abundance)

Answer 1

If 99% is 20 the the total must be approximately 20.

Note: I stated at the top and worked down before realizing you had writer's cramp from all of your questions. This is not a place to dump your homework but for today I have helped with each one. In the future you need to show your work, how you would answer the questions AND especially important is to explain exactly what you don't understand about the problem/question. The more information you provide about what part is troubling you the better I can address your concerns.

Answer 2

20.002

Answer 3

20.002 is the answer given.

Answer 4

20.002