What is the Lewis structure of N2O?

There are three valid Lewis structures in the image attached above.

First is you need to know the valence electrons of the elements involved in the structure. You can do this by either consulting your periodic table or drawing the electron configuration of the respective elements.

From the periodic table, we can glean that the the number of outermost valence electrons for ##N## and ##O## atoms are 5 and 6, respectively.

Next, we need to draw to the possible electron-dot configuration of the substance (based on the valence electrons) and try to calculate the formal charges of each. As ##N_2O## is a substance, the summation of overall charge should be equal to zero.

Also, we need to consider if each or any of those possible structures violate the octet rule (eight electrons per atom).