## Moles vs Number of Molecules

Science questions not covered in Chem 14A and 14B. Try to limit questions to chemistry (inorganic chemistry, physical chemistry, organic chemistry, biophysical chemistry, biochemistry, materials science, environmental chemistry).

Isabelle Fontanilla 1I
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### Moles vs Number of Molecules

In this combustion reaction: CH4 + 2O2 → CO2 + 2H20 (or any chemical reactions, really), I've been hearing people read it as "1 mole of CH4 reacts with 2 moles of Oxygen to produce 1 mole of CO2 and 2 moles of H2O," while some also read it as "1 molecule of CH4 reacts with 2 molecules of Oxygen to produce 1 molecule of CO2 and 2 molecules of H2O."

My question is: Which one is right? Do the coefficients in front of each reactants and products mean moles or molecules/compounds? If it is in moles, does that mean that there are 6.022x10^23 molecules of CH4 present in the reactants side?

Chem_Mod
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### Re: Moles vs Number of Molecules

Both of your interpretations of the chemical equation are correct. The coefficients of the reactants and products indicate the ratio of molecules or moles. Recall that "mole" is another way to express a very large number of molecules (6.022x1023). You can say that 1 mole of CH4 reacts with 2 moles of O2, but you can also say that 6.022x1023 molecules of CH4 reacts with 1.204x1024 molecules of O2.

A De Castro 14B 2H
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### Re: Moles vs Number of Molecules

Both are correct in a way, since 1 mol = 6.022x1023 molecules/atoms/formula units/things. But I believe it is more correct to say "6.022x1023 molecules of CH4" instead of just "1 molecule of CH4".

905096106
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### Re: Moles vs Number of Molecules

I would say moles is a more correct way to say it because the coefficients used in chemical equations represent the ratio in moles within the chemical reaction.

905096106
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### Re: Moles vs Number of Molecules

I would say moles is a more correct way to say it because the coefficients used in chemical equations represent the ratio in moles within the chemical reaction.

Anna O 2C
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### Re: Moles vs Number of Molecules

The stoichiometric coefficients indeed are pertaining to moles of CH4. One mole of CH4 has 6.022x10^23 molecules of CH4, one mole of C, and 4 moles of H. A mole simply refers to the number of objects in a sample, and thus simplifies large quantities of atoms/molecules, just as it's easier to say a dozen eggs vs 12.