What is the molar mass of Fe23  O ?A.  55.85 g/mol                                               B.  120.76 g/molC. 159.67 g/mol                                             D. 11.32 g/mol     2.   Howmany moles are there in 82.5 g of Magnesium sulfate (MgSO4) ?            A.  0.685 moles                                               B.  5.00 moles            C.  1.89 moles                                                 D.  0.989 moles A compound containing iron and sulfur was formed by combining 0.331 g of iron with 0.191 g of sulfur. What is the empirical formula of the compound?                                      A.  FeS4                                              B.  FeS            C.  FeS3                                               D. Fe2S      4.   In unit-4 , you learned writing the formulas of compounds. Since magnesium is a Group 2A element, it forms +2 ions: Mg2+. Since oxygen is a Group 6A element, it forms -2 ions: O2-. So based on these charges, predict the theoretical empirical formula of the compound formed between Mg & O2  A.  MgO2                                B.  Mg2OC.  Mg2O4                               D.  MgO  Health Science Science Nursing CHEM 1020 Share QuestionEmailCopy link Comments (0)