what is the theoretical yield of magnesium oxide when 45.0 g of magnesium and 35.0 g of oxygen react? 2Mg(s)+O2-> 2MgO(s)a) 45.0 g b) 74.6 gc)80.0 gd) 88.2

12. calculate the hydroxide ion concentration of a solution with ph = 3.25. show all calculations leading to an answer

Amixture initially contains a, b, and c in the following concentrations: [a] = 0.300 m , [b] = 1.05 m , and [c] = 0.550 m . the following reaction occurs and equilibrium is established: a+2b⇌c at equilibrium, [a] = 0.140 m and [c] = 0.710 m . calculate the value of the equilibrium constant, kc.

State one important difference between a physical change and a chemical change?