Moles vs Number of Molecules

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Isabelle Fontanilla 1I
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Moles vs Number of Molecules

Postby Isabelle Fontanilla 1I » Thu Oct 04, 2018 12:59 am

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

Postby Chem_Mod » Thu Oct 04, 2018 8:52 am

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

Postby A De Castro 14B 2H » Thu Oct 04, 2018 9:23 am

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

Postby 905096106 » Fri Oct 05, 2018 11:27 am

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

Postby 905096106 » Fri Oct 05, 2018 11:28 am

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

Postby Anna O 2C » Sun Oct 14, 2018 11:48 pm

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.


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