What is this please help

The first element on the periodic table of elements is carbon. a. true b. false

12. complete each of the following word equations for synthesis reactions. a. sodium + oxygen -> b. magnesium + fluorine -> 13. complete and balance the equations for the decomposition reactions. a. hgo -> [with the triangle heat symbol above the arrow] b. h2o(l) -> [with "electricity" written above the arrow]

What is the equilibrium constant of aa+bb=cc+dd