[kristalwithak]

My practice problem states, "How many molecules of ethane, C2H6 are present in .334 grams of C2H6" I understand how to convert the molecular mass to grams then convert the mass(in grams) to moles then from moles to atoms. My answer came out to be, 6.69 x 10^21 C2H6 "atoms." In the back of my book it says that is the correct answer, but obviously as "molecules". I understand that a molecule is an aggregate of 2 or more atoms, but I am confused, is the term molecule and atom used interchangeably if there are 2 or more atoms involved? In other words, it would be correct to say 1 mole = 6.022 x 10^23 atoms/molecules?  Can someone please clarify my understanding... 

[Yggdrasil]

The terms molecules and atoms are not interchangeable.  C₂H₆ is a molecule, and it would be incorrect to call it an atom.  The ethane molecule, however, is composed of two carbon atoms and six hydrogen atoms.  It would also be incorrect to call these carbons or hydrogens molecules.  You will occasionally hear people refer to hydrogen molecules, which refers to the molecule H₂.  Indeed, to distinguish between H and H₂, we often call these atomic hydrogen and molecular hydrogen.

With respect to moles, 6.02x10²³ atoms is a mole of atoms.  6.02x10²³ molecules is a mole of molecules.  6.02x10²³ eggs is a mole of eggs.  It is simply a quantity, like saying 12 of something is a dozen of something.

[kristalwithak]

Thanks!