Question #05458

1 Answer
Feb 21, 2016

Answer:

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"#. 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/

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)#, which means that one mole of copper atoms will have a mass of #"63.546 g"#

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

So, if one mole of copper has a mass of #"63.546 g"# and contains #6.022 * 10^(23)# 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"#.