Question

The electron dot diagram for an unknown element X is shown. What element could this diagram represent?

Answer 1

So like I asked my friend and he said the answer is D.

Answer 2

Answer: D. silicon

Explanation: The electron dot diagram is a diagram that represents the valence electrons of the element as dots.

A. Chlorine: has atomic number of 17 and has 17 electrons. The electronic configuration is:$Cl:17:1s^22s^22p^63s^23p^5$

Thus it has 7 valence electrons.

B. Magnesium: has atomic number of 12 and has 12 electrons. The electronic configuration is:$Mg:17:1s^22s^22p^63s^2$

Thus it has 2 valence electrons.

C. Phosphorous: has atomic number of 15 and has 15 electrons. The electronic configuration is:$P:15:1s^22s^22p^63s^23p^3$

Thus it has 5 valence electrons.

D. Silicon: has atomic number of 14 and has 14 electrons. The electronic configuration is:$Si:15:1s^22s^22p^63s^23p^2$

Thus it has 4 valence electrons.

E. Sulfur: has atomic number of 16 and has 16 electrons. The electronic configuration is:$Si:15:1s^22s^22p^63s^23p^4$

Thus it has 6 valence electrons.