# Difference between 1 mole of CH4 and 1 molecule of CH4?

Is there any difference between 1 mole of CH4 and 1 molecule of CH4? or they mean the same thing?

## Answers and Replies

.Scott
Homework Helper
Certainly. 1 mole of CH4 is Avagardro's number of molecules.

So 1 mole of CH4 is about 16.04 grams.
1 molecule of CH4 is about 0 grams.

Certainly. 1 mole of CH4 is Avagardro's number of molecules.

So 1 mole of CH4 is about 16.04 grams.
1 molecule of CH4 is about 0 grams.
It would be correct If I say ' 1 molecule of CH4 = 16 amu?

It would be correct If I say ' 1 molecule of CH4 = 16 amu?
Well, since carbon's atomic mass is 12.0107 u ± 0.0008 u, and hydrogen's atomic mass is 1.00794 u ± 0.00001 u, the math gives us 16,04246 u ± 0.00084 u for methane, so you are correct.

P.S. I don't know how to use latex, that's why I'm writing in plaintext.

Edit: To elaborate on @.Scott 's answer: an atomic mass unit is just a gram per mole so that means if we multiply a molecule of methane (16.04 u) with a mole, it means 16.04 grams/mole * mole which simplifies to 16.04 grams.

CWatters
Science Advisor
Homework Helper
Gold Member
When you react two elements together you normally want them all used up. You don't want one of them left over contaminating the result. The atomic mass allows you to work out how many grams of each you need to get the right ratio so none is left over.

For example you need 1 mole of sodium and 1 mole of chlorine to make salt with nothing left over. To work out how many grams of each you need to refer to the atomic mass of each. It's a lot easier than counting out the number of molecules you need.

• Spinnor