Balancing equations with fractions  [ENDORSED]

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Alondra Juarez section 1E
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Balancing equations with fractions

Postby Alondra Juarez section 1E » Sat Apr 07, 2018 5:07 pm

Balancing equations can be quite confusing when fractions get involved for me. For example for the chemical equation NH3+O2--------->NO+H2O I balanced it and obtained the answer 2NH3+(5/2) O(2)-------->2NO+3H2O, could I leave the fraction or would I have to multiply the whole equation by two in order to get rid of the fraction?

Sunjum Singh 1I
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Joined: Fri Apr 06, 2018 11:05 am

Re: Balancing equations with fractions  [ENDORSED]

Postby Sunjum Singh 1I » Sat Apr 07, 2018 6:07 pm

Normally having a fraction isn't ideal, but you're right about multiplying the whole equation by 2 in order to cancel out the fraction and make everything whole numbers. So it would become 4NH3+5O(2)---->4NO+6H20 I believe.

Emma Leshan 1B
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Re: Balancing equations with fractions

Postby Emma Leshan 1B » Sat Apr 07, 2018 7:40 pm

Definitely multiply the whole thing by 2. Dr Lavelle said in class that stoichiometric coefficients should be whole numbers.

Alma Flores 1D
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Re: Balancing equations with fractions

Postby Alma Flores 1D » Sun Apr 08, 2018 12:58 am

Yes, you have to multiply by 2 to cancel out the fraction. The stoichiometric coefficients should be whole numbers, not fractions.

Isabella Barkett 1G
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Re: Balancing equations with fractions

Postby Isabella Barkett 1G » Sun Apr 08, 2018 10:30 am

Also it is easier to use whole numbers as it would be simpler to decipher the mole ratio between reactants and products.

Amir Akhavan 1E
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Joined: Fri Apr 06, 2018 11:01 am

Re: Balancing equations with fractions

Postby Amir Akhavan 1E » Sun Apr 08, 2018 3:33 pm

Stoichiometric coefficients should be whole numbers so therefore you should multiply all coefficients by 2. This would make the equation easier to understand as there would be no messy fractions.

Jade Corpus-Sapida 1G
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Re: Balancing equations with fractions

Postby Jade Corpus-Sapida 1G » Sun Apr 08, 2018 5:19 pm

I think this idea is also similar to when we create the empirical formulas. The idea to keep the stoichiometric coefficients whole numbers. For example, if after dividing the moles of a particular element by the smallest number of moles there is still a fractional number, then you would also multiply it by any number in order to find the closest whole number.

Faisal Alshamaa - 1L
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Joined: Fri Apr 06, 2018 11:01 am

Re: Balancing equations with fractions

Postby Faisal Alshamaa - 1L » Sun Apr 08, 2018 11:07 pm

I think it is best to have the coefficients be whole numbers and not fractions. However, it is also important to remember that if you are asked something like how many moles of the other reactant (oxygen) are needed when there are only two moles of ammonia the answer would then be (5/2) or 2.5 .

Paywand Baghal
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Joined: Fri Apr 06, 2018 11:01 am

Re: Balancing equations with fractions

Postby Paywand Baghal » Wed Apr 11, 2018 2:11 pm

All stoichiometric coefficients should be whole numbers and in order to cancel out the two, you can multiply the entire equation by 2. By doing this, you must multiply 2 to every single part of the equation and not just the coefficient fraction you are trying to make whole.

Jamie Reniva 1J
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Joined: Wed Nov 15, 2017 3:00 am

Re: Balancing equations with fractions

Postby Jamie Reniva 1J » Wed Apr 11, 2018 4:19 pm

Stoichiometric coefficients shouldn't be in fraction form because I think that it would indicate that you have to split an atom in half and that's not possible. It is better if you multiply the whole equation by 2.

YeseniaGomez_1L
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Re: Balancing equations with fractions

Postby YeseniaGomez_1L » Wed Apr 11, 2018 10:15 pm

The coefficients must be in whole numbers so you would have to multipy the whole equation (both sides, like in a math problem) by 2 to get rid of the fraction.

Elana Weingord 1C
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Re: Balancing equations with fractions

Postby Elana Weingord 1C » Thu Apr 12, 2018 12:35 pm

It might be easier to begin with the mole ratios in fractions, but the final answer must be given in whole numbers. Using whole numbers is important because when converting atoms needed etc. it is easiest to use whole numbers in the conversions.

Rummel Requerme 1E
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Re: Balancing equations with fractions

Postby Rummel Requerme 1E » Sun Apr 15, 2018 10:19 pm

It's bad style (actually, even looked down upon by scholars) to be leaving fractions in the equation. Multiply both sides by whatever number, in this case, the number 2, and leave whole numbers.

Jose Munoz 1D
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Joined: Tue Nov 14, 2017 3:00 am

Re: Balancing equations with fractions

Postby Jose Munoz 1D » Sun Apr 15, 2018 10:22 pm

You could leave it like that, however it would just make your life more difficult going forward, that best thing would be for there to be whole numbers.


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