Question

1. which electron configuration is of an unreactive element? ne3s2 xe6s2 4f14 kr5s2 4d10 5p6 ar4s2 3d10 14) which element can achieve stability in a molecule without achieving an octet of valence electrons? magnesium hydrogen oxygen bromine

Explanation:

1. Unreactive elements are noble - gases which have a full outer - shell electron configuration. The electron configuration [Kr]5s2 4d10 5p6 represents a noble - gas (xenon). The other configurations do not represent noble - gases.
2. Hydrogen achieves stability with 2 valence electrons (duet rule) instead of an octet. Magnesium, oxygen, and bromine typically follow the octet rule to achieve stability.

Answer:

1. [Kr]5s2 4d10 5p6
2. hydrogen