Write formulas for compounds formed from these pairs of ions:
1. ba2+, s2-
2. b. li+, o2-
3. ca2+, n3-
4. cu2+, i-

yes

explanation:

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answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

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