This is inspired by the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles, now with numbers.

If a number conforms to a special rule, I call it a Chemical Number™.

Use the following examples below to find the rule:

enter image description here

Why are these called chemical numbers?

Hint 1:

These are not Chemical Numbers™: 407.2324, 49284, 40236,3481


A Chemical Number™ appears to be one

whose square root is rational. All of the numbers on the left side have rational square roots: 9.01, 10.8, 79.9, 103, 195, and 238.

  • 5
    $\begingroup$ That doesn't address the 'chemical' part. It looks like rot13/ ngbzvp znff is a relevant part of the puzzle. $\endgroup$ May 14 '20 at 4:03
  • 1
    $\begingroup$ @LannyStrack the question post doesn't ask for the reason for the name. $\endgroup$
    – msh210
    May 14 '20 at 8:33
  • $\begingroup$ Sorry, but how is this chemical? You are on the right track... $\endgroup$
    – Xnero
    May 14 '20 at 8:34
  • 4
    $\begingroup$ @msh210 - True, but it is common on this site in an accepted answer to explain how the title ties in to the question. And not only that, but the numbers used are relevant in this regard as well, so not mentioning it wouldn't really make a complete answer. $\endgroup$ May 14 '20 at 10:24

Finishing up @Deusovi's answer:

A Chemical number is

A number which is the square of a rational number, and that this rational number is the relative atomic mass of a chemical element, correct to 3 significant numbers.


Beryllium > 9.01
Boron > 10.8
Bromine > 79.9
Rhodium > 103
Platinum > 195
Uranium > 238

  • 1
    $\begingroup$ You're close but not quite, what links these elements together? $\endgroup$
    – Xnero
    May 14 '20 at 11:03
  • $\begingroup$ A Chemical Number appears to be as @OmegaKrypton states, but the corresponding rot13(ryrzrag vf fbyvq ng ebbz grzcrengher). $\endgroup$ May 28 '20 at 20:00
  • $\begingroup$ @JeremyDover thanks for the idea but a lot of elements have solid state under room conditions? $\endgroup$ Jun 4 '20 at 6:50
  • $\begingroup$ @OmegaKrypton: Yes, but the numbers given in Hint #1 also meet your criterion, but the OP claims they are NOT chemical numbers. The criterion I suggest above does make the needed differentiation. $\endgroup$ Jun 4 '20 at 11:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.