Calculate the number of atoms present in 52 units of He please ? Chemistry The Mole Concept The Mole 1 Answer anor277 May 31, 2017 #"The relative atomic mass of helium is FOUR"#. Explanation: #"Relative atomic mass"="Mass of atom"/(1/12"th the mass of a """^12C" atom")# #"4 atomic mass units"/("1 atomic mass unit"xx1/12)=4# And multiplication by #"Avogadro's number"# gives the equivalent mass in grams........ So if you have a #52*"amu"# mass of helium, you should reasonably have THIRTEEN helium atoms; unlucky for some. Agreed? Answer link Related questions How do you calculate the number of moles from volume? How do you convert grams to mole? Question #258e5 Question #8d48c Why is the mole an important unit to chemists? What's the mole number? How does the mole relate to carbon 12? How does the mole relate to molecules and ions? How do you calculate the moles of a substance? How can I calculate the moles of a solute? See all questions in The Mole Impact of this question 3519 views around the world You can reuse this answer Creative Commons License