I need help please i need to turn this in today

In a closed or isolated system , matter can not be created or destroyed. it can change forms but is conserved true or false

100 points answer quick 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.

Structure of the atoms: discovery of the nucleus in 1909i need answering all of these questions