Elements in the same period have . the same number of protons
the same number of electron shells
similar properties
the same number of electrons

Me i dont know what to do! the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.

Agas has an empirical formula ch4. 0.16g of the gas occupies a volume of 240cm^3 what is the molecular formula of the me anyone who !

What is the best describtion of the side of the moon that faces earth?