Which reactions are oxidation-reduction reactions? Check all that apply. FeS(s) + 2HCl(aq) → H2S(g) + FeCl2(g) AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3 2C3H6(g) + 9O2(g) → 6CO2(g) + 6H2O(g) Fe2O3(s) + 3CO(g) → 2Fe(l) + 3CO2(g)

When electrons are removed from the outermost shell of a calcium atom, the atom becomes an anion that has a larger radius than the atom. an anion that has a smaller radius than the atom. a cation that has a larger radius than the atom. a cation that has a smaller radius than the atom.