Trong một chu kì, theo chiều tang dần của điện tích hạt nhân,

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.

all eukaryotic cell have mitochondria : )

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)