Don’t mind the incorrect part & da last part for model 3

The second model.

Explanation:

In a Bohr Model, you have your nucleus in the middle, in #1, it's the relatively large black circle, and in #2, it is the large grey dot with the number of protons & neutrons in the center. Now the first ring of a Bohr Model can hold a maximum of 2 electrons. The second ring of a Bohr Model can hold a maximum of 8 electrons. If the element has more than 10 electrons, there will be a third ring (as is shown on your worksheet), and the third ring can hold a whopping 18 electrons!

(Continued from my last answer)

In question #3, the first model follows the orbital rules, as we have 2 electrons on the first ring, 8 electrons on the second ring, and 6 electrons on the third ring. On the other hand, the second model does not follow the orbital rules, as we have 2 electrons on the first ring, only 4 electrons on the second ring, and 10 on the third ring. The mistake here is found on the second ring, as we must hold the max amount of electrons on a ring before moving to the next ring. If the second model were to be correct, it would be shown as 2 electrons on the first ring, 8 electrons on the second ring, and 6 electrons on the third ring.

i dont know

explanation:

a compound is a molecule made of atoms from different elements.

a. by the combination of an unlimited number of elements