CHM 120 Lecture Notes - Lecture 25: Unified Atomic Mass Unit
Document Summary
1 mole of h atoms= 6. 022*10^23 h atoms. 1mole of he atoms = 6. 022*10^23 he atoms. One mole of atoms,ions, or molecules generally make up objects of reasonable size. Ex) 22 copper pennies contain aprroximatly 1 mole of copper (cu) atoms. Ex) 2 large balloons conatin approximately 1 mole of helium (he) atoms. Solution map: mol atoms-- number of atoms * you use avogadro"s # as a conversion factor. 1mol/6. 022*10^23atoms or 6. 022^23atoms / 1mol you have to pick which one to use based on which way will cancel out your units. Ex) calculate the number of iron atoms in 125 moles of iron atoms. 125mol fe* 6. 022*10^23atoms/1mole fe = 7. 53*10^25 fe atoms. Molar mass- the mass of 1 mol of atoms of an element. 1mol c atoms= 6. 022*10^23 c atoms= 12. 01g c (molar mass) or: molar mass c= 12. 01 g/mol. 1 mol s atoms= 6. 022*10^23 s atoms= 32. 07g s (molar mass)
