Final answer:
The formula for barium nitrate cannot be simplified to BaNO6 because Ba(NO3)2 correctly represents the ratio of barium ions to nitrate ions, which is necessary to balance the charges in this ionic compound.
Step-by-step explanation:
The formula for barium nitrate is indeed Ba(NO3)2, where barium has a +2 charge (Ba2+) and each nitrate has a -1 charge (NO3-). When writing the formula for an ionic compound which includes a polyatomic ion like nitrate, one cannot simply combine the elements' symbols and subscripts as done in BaNO6. The formula Ba(NO3)2 indicates that there are two nitrate ions for each barium ion to balance the charges, and for compounds with more than one of the same polyatomic ion, parentheses are used to indicate the number of these ions that are present. Consequently, the formula cannot be simplified to BaNO6.