Yes, OXYGEN is a Scrabble word!

Letter values in Scrabble US: O 1, X 8, Y 4, G 2, E 1, N 1.

Is it a valid word?

OXYGEN is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust

Also: o, atomic number 8.