Balancing Equations Coefficient Question
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Balancing Equations Coefficient Question
Sometimes when I am balancing chemical equations, I end up with coefficients that are not whole numbers. For example, there are 15 mols of O on one side, and on the other side I have to add a coefficient before O2. I can't put 7.5, even though 7.5 * 2 = 15, because I know coefficients have to be whole numbers. Is the best thing to do in this case multiply every coefficient in the reaction by 2? This should preserve the ratio while making everything a whole number?

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 Joined: Wed Sep 30, 2020 9:44 pm
Re: Balancing Equations Coefficient Question
Yes, you would multiply the equation by two in order to make all coefficients whole numbers. Having whole number coefficients makes the equation easier overall to use in future steps.

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Re: Balancing Equations Coefficient Question
Yes, you can't have a half of an atom (unless you want to experience dire consequences), and so in a molecular equation you should scale each coefficient up to the lowest whole number. (eg, 7.5 should become 15, and 2.75 should become 11). If at any point if you write a fraction as a coefficient in a molecular equation, it will be marked wrong.

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Re: Balancing Equations Coefficient Question
Yes the best thing to do would be to multiply the coefficients by two because we want whole numbers, and to answer your second question it will in fact preserve the ratio.

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Re: Balancing Equations Coefficient Question
Yes, you would multiply each coefficient by 2 since the stoichiometric coefficients must be whole numbers. In the notes for this topic, Dr. Lavelle stated how multiplying both sides of the chemical equation by a number does not affect the balance of each atom type.

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Re: Balancing Equations Coefficient Question
Yes, that is exactly right! Using fractions and nonwhole numbers makes it more difficult to solve. And when you multiply by 2 on each side, it does not unbalance the equation because you are doing it to both sides.

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 Joined: Wed Sep 30, 2020 9:36 pm
Re: Balancing Equations Coefficient Question
If your equation has any stoichiometric coefficients that are fractions, you need to convert them to whole numbers. Since you can't have a fraction of a compound, you need to multiply whatever number on one side to the other as well in order for it to be balanced.

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Re: Balancing Equations Coefficient Question
To correctly balance an equation with fractions as stoichiometric coefficients, you must multiply every coefficient with the demoniator of the fraction. This action causes every coefficient (including the faction) to become a whole number.

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Re: Balancing Equations Coefficient Question
Yes that's right, since you would use the lowest value possible that would give you whole numbers for coefficients.

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Re: Balancing Equations Coefficient Question
Yes, you have the right idea about it. since you do not want a coefficient to be 15/2 you have to multiply every coefficient by 2 so they are all in whole numbers and maintain the correct ratio

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 Joined: Wed Sep 30, 2020 10:00 pm
Re: Balancing Equations Coefficient Question
Yeah I would continue doing the same thing you are doing right now since it is much easier to balance the chemical equation.

 Posts: 93
 Joined: Wed Sep 30, 2020 10:03 pm
Re: Balancing Equations Coefficient Question
When that happens, try to multiply it to get the lowest coefficient possible. For instance, if you have 7.5, multiply it by 2 to get 15. If you have 3.33, multiply by 3 to get 10. It's important to look at the decimals to see what number you should multiply by.

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 Joined: Wed Sep 30, 2020 9:42 pm
Re: Balancing Equations Coefficient Question
Yes, you would want to multiply your coefficients by the same number in order to get whole ratios. As long as you preserve the ratio, multiplying the coefficients is fine.

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Re: Balancing Equations Coefficient Question
Yes, you should multiply your coefficients by the same number in order to get whole ratios. That number should be the smallest coefficient possible, or you'll need to simplify. For example, if the coefficient is 1.5, you'd want to multiply by 2. If 3.33, multiply by 3. When you put it in fraction for it's easier to see  3/2 *2 = 3. Don't forget to preserve the ratio of the reactants and products, and you'll be good :)

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 Joined: Fri Oct 02, 2020 12:16 am
Re: Balancing Equations Coefficient Question
As everyone has said, as long as you multiply both by the same number, you should be fine! :)

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 Joined: Wed Sep 30, 2020 9:54 pm
Re: Balancing Equations Coefficient Question
Amanda BuenoKling 2L wrote:Sometimes when I am balancing chemical equations, I end up with coefficients that are not whole numbers. For example, there are 15 mols of O on one side, and on the other side I have to add a coefficient before O2. I can't put 7.5, even though 7.5 * 2 = 15, because I know coefficients have to be whole numbers. Is the best thing to do in this case multiply every coefficient in the reaction by 2? This should preserve the ratio while making everything a whole number?
you just multiply the coefficient by to in order to reach a whole number for the final balance equation.
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