The game is played on an hexagonal grid board using tiles with a periodic element index fill-painted on one side. To begin, each player blindly chooses 7 tiles for their bouquet.

Turns consist of creating a new molecule or modifying an existing molecule, by adding or inserting tiles. Tiles already on the board may be moved or removed to accomodate the change.

Unlike word Scrabble, a new molecule can be started anywhere. Adjacent tiles in a molecule indicate an atomic bond (actual geometry is otherwise ignored).

At the end of a turn, all molecules on the board must be viable.

Scoring:
• +points: tiles played plus existing tiles in the molecule which haven't been moved;
• -points: removed tiles.
As in word Scrabble there are multiplier squares (err "hexes"), valid for the first covering by a tile.

The face value of the tiles is a rough reciprocal of the element's affinity to formation. (Noble gases have a higher value if they're in a molecule, rather than played in their monatomic state.)

At the end of a turn, the player takes enough tiles from the bag to bring his/her bouquet up to the minimum of 7 pieces. (Since tiles removed during play are put into the bouquet the player may already have 7 or more pieces)

----

Variation: Entropic Scrabble - as above, but scoring is based on energy of formation.
-- FlyingToaster, Jan 16 2016

Sokobond http://www.sokobond.com/
Another Chemistry-themed puzzle game. [Cuit_au_Four, Jan 18 2016]

Perhaps one might attempt to form a chain, such as a polymer or polypeptide? Could have side chains, can add to any end of the chain.
-- Vernon, Jan 17 2016


hmm... true, multiple repetitive elements probably shouldn't count towards the score, nor the main chain if a sidechain is being added to...

So, building methane from a previously laid carbon atom gets you points, as does making ethane from methane, but making propane only gets you ethane points, or maybe only added-tile points.

Similarly to word Scrabble where, just because a sequence of letters is pronounceable doesn't mean it's a recognized word, all molecules must be referenced in a chemistry handbook. (Or, perhaps, undocumented yet viable molecules don't receive scoring)
-- FlyingToaster, Jan 17 2016


I like it +1

And it turned out to be more novel than my periodic table dartboard...if it wasn't for those pesky kids...
-- not_morrison_rm, Jan 18 2016


Well, your dartboard could be used in conjuction with the Scrabble board: the player throws darts to see which elements he/she gets.
-- FlyingToaster, Jan 18 2016


You could also play this like regular scrabble, except that:

(1) Element names instead of letters
(2) Tiles for subscripts 1, 2 etc
(3) Open and close bracket tiles
(4) All compounds (including those created by intersection) must be viable and written in standard notation.
-- MaxwellBuchanan, Jan 18 2016


Would an organic chemistry edition be viable?
-- Ling, Jan 18 2016


I think there's certainly enough room to play with a benzene ring.
-- FlyingToaster, Jan 18 2016



random, halfbakery