1. Why is it important to take the temperature of the closed system(the box) and the ice water before we start the demonstration?

It is important to take the temperature of your materials before you begin a demonstration so you can see the change in particle movement as you do the demonstration or after you finish.

the answer is d.) potassium

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.