A mole of a pure substance contains 6.02x10^23 atoms. Alway true, sometime true or never true?

Question

-I was thinking sometime true since a pure substance can be like H2O but H2O have 3 "atoms" (Is this what you call individual part of H2O?). Each "atoms" have 6.02E23 so it wouldn't be 6.02E23 atoms. Thanks

Answer 1

Sometimes true.