[IBM]

You were told several times there is no such thing as just a "C molecule", you need to mark it with the correct formula. Ignoring what you are told you are wasting time of those that try to help you.

1. 2 (single) atoms of C

3. 2 moles of C atoms

5. 24 gram of C atoms

All of these can be correct, although not at the same time.

1. Could you explain when these can be correct?
2. Do 2 atoms of C and 2 mole of C atoms same as 24 grams of C atoms?

[Arkcon]

http://www.chemicalforums.com/index.php?topic=94956.msg336972#msg336972

[IBM]

''2 volume of hydrogen + 1 volume of oxygen = 2 volume of water vapour''
Now my question is how many hydrogens molecules there in 2 volume of hydrogen?

[Borek]

As long as the volume is not defined exactly (say, 1 L, or 2 m³) you don't know and can't calculate.

What you do know is what will be the ratio of reacting and produced volumes of gases.

[IBM]

As I know one-mole of CH4 molecules = 6.023 X 10^23 CH4 molecules and one molecule of CH4 = one C atom and 4 H atoms bonded together.
the molecular mass of CH4 = 16 amu and the molar mass of CH4 = 16g/mole
The what is the difference between one mole of CH4 and one molecule of CH4? or there is no difference but the unit only? Please explain it. Please point out my mistakes if I am wrong. 

[Arkcon]

Hi there, IBM:, I've gone and merged many of your posts together.  You seem to be asking the same question again and again, and not using the help you've gotten already to build your skills.  Try to read this entire thread, and try to see if there's something you still don't understand, and ask questions that grow your knowledge.