The greatest number of valence electrons available for bondinging is Chlorine.
I'm pretty sure the answer is a <em>dune</em>. Many sandy deserts are filled with sand dunes because of the wind.
The hydrogen will react with 12 g B
Mass of B = 3.3 g H_2 × (3.6 g B/1.0 g H_2) = 12 g B
