What happens to the molecules of a substance during a chemical change? The molecules in the substance get larger or smaller.
During a chemical change, the substance's molecules stay the same.
Some molecules melt when they are combined with other molecules.
Bonds in the molecules are made or broken to form new molecules.

What layer of the atmosphere is directly above the troposphere?

Which atom or ion is the largest? a. k b. k+ c. ca d. ca2+ e. li

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.