The electron dot diagram shows the arrangement of dots without identifying the element.

Question

? with 2 dots above and 1 dot each right, below, left.

Which element’s symbol could replace the question mark in the diagram?

boron (B)
neon (Ne)
rubidium (Rb)
arsenic (As)

Answer 1

The electron dot diagram you've described, with 2 dots above and 1 dot each to the right, below, and left, represents an element with 5 valence electrons. This configuration corresponds to the element boron (B), which has 3 valence electrons in the 2s and 2p orbitals.

However, the element with the specific arrangement you mentioned actually has a total of 5 valence electrons, which is characteristic of arsenic (As). Therefore, the element that could replace the question mark in the diagram is arsenic (As).