what volume (in l) of a 1.25 m
potassium fluoride (kf) solution
would be needed to make 455 ml of
a 0.838 m solution by dilution?

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.

he would use the colour black

here are some of the ways in which chemical and nuclear reactions differ.

explanation: