Explain the significance of duration of exposure from a toxicity point of view. What are the term used to described the different ranges of exposure

Toxic exposure can be defined as the exposure of a toxin or poison and when it gets imbibe or absorbed in the body of a person and get circulated to all the parts of the body through blood circulation.

Explanation:

A person may get exposed to the toxin either accidentally or for a purpose. The toxin can also be used a weapon to kill another person. There are two main kinds of exposure acute and chronic. The acute exposure of the toxin may remain for a short period of time and the chronic exposure is for prolonged period. Sometimes acute poison can cause instant death and the chronic poison shows a later profound impact on the body with daily intake of some amount of poison. Levels of toxicity can be defined as the different ranges of exposure of toxic.

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.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8