Problem 83AE

Consider the stable elements through lead (Z = 82). In how many instances are the atomic weights of the elements in the reverse order relative to the atomic numbers of the elements? What is the explanation for these cases?

Lecture #1 8/22/2017 1 Prove that a number is rational if its decimal representation becomes periodic. (Repeated 0's is periodic. A rational number can be represented as a fraction which has an integer as a numerator and denominator. When dividing two integers x and y the denominator y will either have a remainder of 0 in which case the decimal form will contain a repeating 0 or it will have some remainder, z that is never y < z. Considering this there are only y possibilities for the remainder in each new decimal meaning that it will repeat (become periodic) in < y decimal places. 1 Write the number 0. 25 as a ratio of two integers Let x = 0. 25 Then 100x = 25. 25 = 25 + x ⇒ 9