Question #05458

1 Answer
Feb 21, 2016

Let's find out!

Explanation:

Atoms are very, very tiny things, so in order to be able to determine the mass of a single atom you need to know the mas of a mole of atoms.

A mole is simply a very, very large collection of atoms, larger enough so that the mass of one mole of atoms can have sense for us.

So, pick up a periodic table and look for copper, "Cu"Cu. You will locate it in period 4, group 9. Take a look at its molar mass, which is written below the element's chemical symbol

![http://sciencenotes.org/copper_tile/](useruploads.socratic.org)

That number tells you the mass of one mole of copper atoms, i.e. copper's molar mass. Copper has a molar mass of "63.546 g mol"^(-1)63.546 g mol1, which means that one mole of copper atoms will have a mass of "63.546 g"63.546 g

Now, in order to have one mole of copper, you need to have exactly 6.022 * 10^(23)6.0221023 atoms of copper - this is known as Avogadro's number.

So, if one mole of copper has a mass of "63.546 g"63.546 g and contains 6.022 * 10^(23)6.0221023 atoms of copper, you can say that one atom of copper will have a mass of

1color(red)(cancel(color(black)("atom of Cu"))) * overbrace((1color(red)(cancel(color(black)("mole of Cu"))))/(6.022 * 10^(23)color(red)(cancel(color(black)("atoms of Cu")))))^(color(Purple)("Avogadro's number")) * overbrace("63.546 g"/(1color(red)(cancel(color(black)("mole of Cu")))))^(color(blue)("copper's molar mass")) = color(green)(1.055 * 10^(-22)"g")

So the answer to your question is yes, one atom of copper has a mass of 1.055 * 10^(-22)"g".