2Mg + O2 → 2MgO How many grams of MgO are produced when 40.0 grams of O2 react completely with Mg?

101 g

Explanation:

M(O2) = 2g*16.0 = 32.0 g/ mol

M(MgO) = 24.3 + 16.0 = 40.3 g/mol

                                   2 Mg          + O2            →      2MgO

from reaction                               1 mol                  2 mol

from reaction                    1 mol*32.0 g/mol            2 mol*40.3 g/mol

given                                          40 g                        x g

1 mol*32.0 g/mol     ---       2 mol*40.3 g/mol

            40 g          ---              x g

x = (40*2*40.3)/(1*32.0) = 100.75 g ≈ 101 g

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.