Not necessarily. The vow of chastity would be covered in the Word of Wisdom, the BOM is more scriptural.
(not mormon but 90% sure on that one)
The Word of Wisdom refers to what people eat. It prohibits the consumption of too much meat, except in winter, and bans coffee, tea, alcohol. Here's the excerpt from Wikipedia:
The "Word of Wisdom" is the common name of a section of the Doctrine and Covenants,[1] a book considered by many churches within the Latter Day Saint movement to consist of revelations from God. It is also the name of a health code based on this scripture, practiced most strictly by The Church of Jesus Christ of Latter-day Saints (LDS Church) and Mormon fundamentalists, and to a lesser extent, some other Latter Day Saint denominations. In the LDS Church, compliance with the Word of Wisdom is currently a prerequisite for baptism, service in full-time missionary work, attendance at church schools, and entry into the church's temples; however, violation of the code is not considered to be grounds for excommunication or other disciplinary action.[2]
The text discourages "hot drinks", the non-medicinal use of tobacco, the consumption of wine (excluding sacramental wine) or "strong drinks", and encourages using meat sparingly. The scripture also recommends the consumption of herbs, fruits, and grains, as well as grain-based "mild drinks". As practiced by the LDS Church, there is no firm restriction relating to meat consumption, but there are additional restrictions against narcotics, and all alcoholic beverages are forbidden, including beer. The LDS Church interprets "hot drinks" to mean coffee and tea.
The Book of Mormon is tells the story of Jews who allegedly came to America and became the ancestors of today's American Indians. A large part of it is the King James Bible, including the condemnation of polygamy.
The Word of Wisdom is in the Doctrine and Covenants, which is a set of "modern" scriptures which supersedes previous scriptures. It establishes polygamy and explains other beliefs, such as the nature of Diety. Both the Book of Mormon, the Doctrine and Covenants and other Mormon scriptures have been massively edited and rewritten over the years.
None of them support any of the sexual practices Jodi Arias said she believed were "all right." Also, the Law of Chastity would be discussed at Family Home Evening and many other church meetings that she attended. There is absolutely no possibility that she is telling the truth that she didn't know anal and oral sex were not ok with the church.