Give an example of a situation where a color change occurs, but not because of a chemical reactions?

What layer of the atmosphere is directly above the troposphere?

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.

At element makes up all organic compounds?