Answer:
(a) O = Valance Electrons (6), Inner electrons (8)
(b) Sn = Valance Electrons (2), Inner electrons (36)
(c) Ca = Valance Electrons (2), Inner electrons (20)
(d) Fe = Valance Electrons (2), Inner electrons (26)
(e) Se = Valance Electrons (6), Inner electrons (34)
0.289 moles of MgCl2
Explanation:
(27.5 g MgCl2) x (1 mol MgCl2 / 95.211 g MgCl2) = 0.289 moles of MgCl2
2.04 moles
Since the ratio of Na2O to NaOH is 1:2, you multiply the number of moles by 2, equaling 2.04 moles.