What is a residual? what does it mean when a residual is positive?

What three things determine the shape and size of a puddle when water is poured out onto a surface

For the reaction shown, find the limiting reactant for each of the following initial amounts of reactants. 4al(s)+3o2(g)→2al2o3(s) a) 1 molal, 1 mol o2 b) 4 molal, 2.6 mol o2 c) 16 molal, 13 mol o2 d) 7.4 molal, 6.5 mol o2

The same side of the moon always faces earth because the