Why does the seneca falls declaration object to “a different code of morals for men and women”?

The Seneca Falls Declaration objects to "a different code of morals for men and women" because the purpose of the declaration was to achieve equallity between men and women.

Explanation:

The Seneca Falls Declaration is the document resulting from the convention held on July 19 and 20, 1848 signed by sixty-eight women and thirty-two men from various political movements and associations of liberal nature and near the abolitionist circles, led by Elizabeth Cady Stanton and Lucretia Mott to study the conditions and social, civil and religious rights of women.  

It was Elizabeth Cady Stanton who was in charge of drafting the statement of principles and the resolutions that were finally approved. In her writing, she adopted the form of the Declaration of Independence, with which she managed to load it with a powerful force of conviction and historical significance.