Answer: barium oxide
Explanation: The barium will give some of it's electrons up to the oxygen, and then they will both reach the stability of a noble gas. Then, they will both combinate to barium oxide, so the answer is barium oxide.
90 grams due to laws of conservation of mass. Output mass = input mass. Mass can never be created or destroyed.
So let's convert this amount of mL to grams:

Then we need to convert to moles using the molar weight found on the periodic table for mercury (Hg):

Then we need to convert moles to atoms using Avogadro's number:
![\frac{6.022*10^{23}atoms}{1mole} *[8.135*10^{-2}mol]=4.90*10^{22}atoms](https://tex.z-dn.net/?f=%20%5Cfrac%7B6.022%2A10%5E%7B23%7Datoms%7D%7B1mole%7D%20%2A%5B8.135%2A10%5E%7B-2%7Dmol%5D%3D4.90%2A10%5E%7B22%7Datoms%20)
So now we know that in 1.2 mL of liquid mercury, there are
present.
A coefficient is a whole number that appears before the formula in an equation.
If it’s multiple answers then it’s A,C,D. If it’s only one answer then your best answer is A. Because you always report accidents to an authority so that they can figure out how to solve the problem.