Which changes are evidence of a chemical reaction? a beaker of water becomes hot to the touch upon?

List four observations that indicate that a chemical reaction may be taking place

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.

What state of matter is ice a. liquid b. element c. solid d. gas