Everything in red i need help with Standardization of KMnO4

***Everything in red i need help with****

Standardization of KMnO4                                                                           Determination of Iron

                                                                    Trial 1              Trial 2                                                          Trial 1           Trial 2

Mass of H2C2O4H2O(MW=126 g/mol),g    0.25                 0.25                   Mass of unknown,g            0.80                0.80

Inital buret reading, ml                                 0                      0                        Inital buret, ml                     0                      0

Final Buret Reading,ml                                 43                    42                     Final buret, ml                     23                   26

Volume of KMnO4 used,ml                          43                    42                   Volume of KMnO4 used, ml   23                   26

Moles of Oxalic acid used                           0.002               0.002                 Moles of   \" used                  3.0                  6.0

Moles of KMnO4 used                                 ?                      ?                      Moles of Iron in sample    ?                     ?

Molarity of KMnO4 Soultion                         ?                      ?                     mass of iron in sample, g ?                     ?

                                                                                                                        Percent of iron sample ?                ?                               

Solution

no. of moles of KMnO4 = 2 * moles of Oxalic acid

beacuse oxalic acid is a dibasic acid

Moles of KMnO4 = 0.004(in both the cases)

Molarity of KMnO4 = 0.004/0.043 = 0.0930 (Trail 1)

Molarity of KMnO4 = 0.004/0.042 = 0.09520 (Trail 2)