OpenStudy (ibrafacts):

Can some teach me how to find the formula please:( I give medal too

OpenStudy (ibrafacts):

i have a test tomorrow someone please teach m

OpenStudy (frostbite):

Is it a), c) and d) causing issues?

OpenStudy (ibrafacts):

yeah

OpenStudy (ibrafacts):

i mean if u teach me how t do a i try b and c again and u check it

OpenStudy (frostbite):

I like that! (you are the first person who haven't just wanted an answer AKA I like you per definition!) Okay: a) Barium makes a divalent cation (2+), while oxygen makes a divalent kation (2-). We make this deduction on the idea that both barium and oxygen wants perfect gas configuration, thus barium needs to lose 2 electrons and oxygen needs to gain 2 electrons as you can see in the periodic table. The whole compound need to be electronic neutral (no charge) thus we can get the stoichiometry of the molecule to be: BaO

OpenStudy (ibrafacts):

how do u know oxygen is +2?

OpenStudy (ibrafacts):

i showed u my periodic table it doesnt say it

OpenStudy (frostbite):

How many electrons does oxygen need to obtain perfect gas electron configuration?

OpenStudy (ibrafacts):

Oh I see never it says -2

OpenStudy (ibrafacts):