How many moles are in 3.45 g of Na2O?Round your answer to three significant figures. IN A FINAL EXAM HURRY PLEASE

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.

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

Avariable that is not being directly tested during an experiment should be