atomic number
Protons....
crossword puzzle
Where is the crossword puzzle?
a Sudoku puzzle is a test of logic while a crossword puzzle is a test of how like a thesaurus you are or a test of general knowledge. which one if better is a matter of opinion, but i suppose one might stimulate the brain than the other, if that is what you mean by better.
American Crossword Puzzle Tournament was created in 1978.
crossword puzzle
There are a great many number of hard word puzzles that use syllables. One puzzle that does his is a crossword puzzle.
Even number/odd number
That's not really a question... a crossword puzzle using mathematical terms is still a crossword puzzle. If you're looking for such a puzzle in particular, just google "math crossword" and you'll get a number of sites offering free math crossword puzzles.
no
who
There are many great internet sources where information about crossword puzzle dictionaries can be found. Webster crossword puzzle dictionary is one of these great sources.