Which sample contains the greatest number of atoms?

1 Answer
May 7, 2017

Well one mole of #NO_2# contains three moles of individual atoms......so the answer we want is #d.#

Explanation:

Let's try something, we know that the mole #-=6.022xx10^23# items of stuff. For the purposes of this question, let's say the mole was a round dozen, i.e. 12 individual items.

And we rewrite the question to give:

#"How many ATOMS are there in the following quantities?"#

#"a. ONE dinitrogen molecule"#;

#"b. 1 DOZEN dinitrogen molecules"#;

#"c. ONE"# #NO_2# #"molecule"#;

#"d. ONE DOZEN nitric oxide molecules"#.

So instead of the mole, I have used another VERY POPULAR collective number, the dozen. And the dozen is commonly used because I can keep a tally with my thumb and the finger joints of the ONE HAND.

And so for #"a, b, c, d,"# I can write the answers as #2,24,3,36.# Clearly #d.# CONTAINS the most number of atoms. Are you following me? And in the question you were asked, you replaced the #"dozen"# with another (MUCH LARGER) collective number, #"the mole"#, which is specified to be equal to #6.022xx10^23#. It is important that you incorporate this idea of moles into your understanding. It will save you a lot of grief.

See this answer and here for another spray.