Which of the following has the greatest mass, in grams?
a. 1 atom of gold (au)
b. 1.0 mol mercury (hg) atoms
c. 2.0 mole of chlorine (cl) atoms
d. 25 atoms of mercury (hg)

Which diagram shows the correct way to represent an ionic compound of magnesium oxide?

For the reaction shown, calculate how many moles of no2 form when each of the following completely reacts. 2n2o5(g)→4no2(g)+o2(g) part a 1.0 mol n2o5 express your answer using two significant figures. nothing mol m o l request answer part b 5.4 mol n2o5 express your answer using two significant figures.

The empirical formula of a compound is ch2o and its mass is 120 amu/molecule, what is its formula?