Which of the following has the greatest mass, in grams? a)0.3 mol iron fe b)1 atom silver ag c)25 atoms lead pb d)1 mole of hydrogen atoms h

Since we are given the amount of moles of each element, to calculate for the mass we need to remember that:

Mass = Molar mass * Moles

Moles = Atom / (6.022*10^23 atoms / mole)

6.022*10^23 atoms / mole is the Avogadro’s constant to convert atoms to moles.

So when atoms are given: Mass = Molar mass * Atom / 6.022*10^23

Searching for the molar mass of each element in the periodic table:

Iron (Fe) = 55.85 g / mol

Silver (Ag) = 107.87 g / mol

Lead (Pb) = 207.2 g / mol

Hydrogen (H) = 1 g / mol

Therefore calculating for the mass:

A. Mass of Fe = (55.85 g / mol) * 0.3 mol

Mass of Fe = 16.76 g

B. Mass of Ag = (107.87 g / mol) * 1 atom / (6.022*10^23 atoms / mole)

Mass of Ag = 1.8 * 10^-22 g

C. Mass of Pb = (207.2 g / mol) * 25 atom / (6.022*10^23 atoms / mole)

Mass of Pb = 8.6 * 10^-21 g

D. Mass of H = (1 g / mol) * 1 mol

Mass of H = 1 g

Therefore 0.3 mol of iron has the greatest mass among the 4 elements.

 0.3 mol of iron Fe

increased stability in the completion of fluorine's outer shell.