7.2 mol H × (1 mol H_2SO_4/2 mol H) = 3.6 mol H_2SO_4
Change of appearance, change in size and shape of a substance, change in phase of a substance, and I'm pretty sure expansion/contraction is an answer, too.
20 grams of borax contains (20.0g) / (201 g mol -1) =0.10 mol of borax.
Therefore 0.40 mol of borax
B. A bond between two atoms: it doesn't matter if it's positive or negative or neutral, if there is a bond between two atoms, it is covalent.
