Balancing reactions tips

longjump
Posts: 29
Joined: Fri Sep 28, 2018 12:17 am

Balancing reactions tips

Does anyone have any good tips or tricks for solving balancing reaction questions? Writing the numbers out and calculating every guess works eventually but I feel like there is a faster way.

Nicole Lee 4E
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Joined: Fri Sep 28, 2018 12:16 am
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Re: Balancing reactions tips

I try to balance all other elements before balancing oxygen and hydrogen. If there are polyatomic ions within the problem, I balance those first, treating them as one unit.

Catherine Kim 3K
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Joined: Fri Sep 28, 2018 12:26 am

Re: Balancing reactions tips

A tip that I use is to first balance the element that occurs the least.

KarlaArevalo2F
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Re: Balancing reactions tips

Something I always do when balancing is I always write down each element on both the reactant and product sides along with the amount of each there is and add a coefficient accordingly to balance both sides. Image added just in case wording isn't clear.

Jasmine Chow 1F
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Re: Balancing reactions tips

When I balance equations I like to write the number of elements on both sides so I can see everything visually.

B2O3+Mg ------> MgO+B

B:2 B:1
O:3 O:1
Mg:1 Mg:1

Then you can see where to balance everything out.

Phoebe Chen 4I
Posts: 55
Joined: Fri Sep 28, 2018 12:29 am

Re: Balancing reactions tips

You could draw a table of the different atoms and have a column for reactants and products. Then make sure that they equal the same amount. Separate the individual atoms instead of trying to visualize them as molecules.

Abhi4F
Posts: 30
Joined: Fri Sep 28, 2018 12:28 am

Re: Balancing reactions tips

I tend to find the element that occurs the least and balancing from there as it makes the process way easier.

Minsub Lee 3E
Posts: 32
Joined: Fri Sep 28, 2018 12:25 am

Re: Balancing reactions tips

I will usually check to see which elements do not need balancing. Then I will start to balance the element that occurs the least. If adding a stoichiometric coefficient causes another element in that same molecule to be unbalanced, I would balance that. I usually just do that step-by-step.

Arshia Ramesh 1G
Posts: 35
Joined: Fri Sep 28, 2018 12:18 am

Re: Balancing reactions tips

I usually start by writing all of the coefficients on the side of the reaction that they occur.
Then I continue balancing both sides starting with the element in the least amount.

Posts: 30
Joined: Fri Sep 28, 2018 12:26 am

Re: Balancing reactions tips

Also when you are balancing an equation that involves diatomic molecules, such as O2 and you need an odd number of Oxygens on one side, something that has worked for me is to keep fractional coefficients until the equation has the same number of moles of each element on each side, and then multiply by a common denominator to create all whole number coefficients.

Lauren Huang 1H
Posts: 60
Joined: Fri Sep 28, 2018 12:16 am

Re: Balancing reactions tips

Make sure to double check your answer before you move on! Sometimes I make a couple of arithmetic mistakes without knowing, so make sure you check that both sides have the same number of elements.

Xingzheng Sun 2K
Posts: 62
Joined: Fri Sep 28, 2018 12:29 am

Re: Balancing reactions tips

From my experiences, I usually start with the element that is the least common to the most common or easiest. By meaning the easiest, for example, H2 can be the one because it will be balanced easily so that I leave it for the latest. After you have the fixed number of the least common element, try to make the other elements in the same compound equal.

Sona Hakobyan 3J
Posts: 45
Joined: Fri Sep 28, 2018 12:25 am

Re: Balancing reactions tips

I start with whichever element is in the equation the least. Also I tend to do single elements last for example O2 or H2. This way you get everything out the way and however many O's or H's there turn out to be in the different products or reactants, it wont matter because we can account for them without changing the equation again using our single element. For example if it wasn't a single element and it was rather SO4, once we apply the coeffecient, it would also affect the S which might cause us to restart the balancing process.

Elena Saab 4A
Posts: 43
Joined: Fri Sep 28, 2018 12:27 am

Re: Balancing reactions tips

What helps me the most is to first balance the elements that occur the least, and then I move on to elements other than Oxygen and Hydrogen. I save elements that are not combined with anything other than itself for last!

Abby De La Merced 3F
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Re: Balancing reactions tips

My TA advised that your best bet with balancing equations properly and efficiently was to alway balance the single element last as its the easiest to manipulate when all the other parts of the balancing are done. And start with the least occurring element too.

annaspain
Posts: 32
Joined: Fri Sep 28, 2018 12:24 am

Re: Balancing reactions tips

I find it much easier to make sure my work is correct when I can have clear visuals to make sure everything is balanced. I usually keep a running tally while I'm balancing my equation for each individual element, which makes the process much easier to keep track of for more complex equations.

RoopshaChatterjee 1G
Posts: 30
Joined: Fri Sep 28, 2018 12:17 am

Re: Balancing reactions tips

When balancing equations I find it helpful to list out the different elements on each side and tackle each element individually as I go. I re-write the equation with the coefficients I'm trying in order to keep my work organized so I don't get confused.

Samantha Chung 4I
Posts: 77
Joined: Wed Oct 03, 2018 12:16 am

Re: Balancing reactions tips

I usually pick one atom to start with then deduce the rest accordingly. There was a problem we did today in discussion where we wrote one of the ratios as a fraction(I think it was 25/2). Then we multiplied the entire thing by two to get integer values. I think thats useful as well!

Mayaal_Khan_4H
Posts: 41
Joined: Fri Sep 28, 2018 12:28 am

Re: Balancing reactions tips

I would suggest writing the numbers down under the reaction sign and solving them right there. I will provide you with an example:
So, balance H2 + O2 ------> H2O by writing down the numbers of moles each reactant and product has. Having the moles written down
2 =H= 2
2 =O= 1
makes it easy for you to balance the equation. So, the final step would be to equalize both sides.

Posts: 63
Joined: Fri Sep 28, 2018 12:19 am

Re: Balancing reactions tips

I usually start with what occurs the least and work through trial and error if I have to. It something is taking too long or not working out make sure you wrote it down correctly because a small mistake at first can turn into a huge hassle in the long run.

SydBenedict2H
Posts: 60
Joined: Wed Nov 08, 2017 3:00 am

Re: Balancing reactions tips

Typically I do it by trial and error as wel (more or less logic-ing it out) but you can do the method from that one example he did where he got 13/2 (6.5) then multiply both side by 2

Anjali 4A
Posts: 59
Joined: Fri Sep 28, 2018 12:28 am

Re: Balancing reactions tips

I also usually balance equations using the trial and error method, but like Dr. Lavelle said in class we should always balance the element that occurs the least in the equation. For example, if O Occurs in many species (e.g. 3) and H & C occurs in less species (e.g. 2) we should balance O first then the following two.

jane_ni_2d
Posts: 67
Joined: Fri Sep 28, 2018 12:23 am

Re: Balancing reactions tips

I balance the equation based on whether the elements are in a compound or not! I balance the elements in compounds first, because the elements not in compounds or in compounds of just themselves (ex: O2) are easier to change around later.

Timothy_Yueh_4L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

Re: Balancing reactions tips

I typically balance equations starting off with elements that has the least amount of atoms, and then begin balancing the rest in order of least to most. When dealing with combustion, I again begin with the element with the smallest amount (C, N, etc.) and work my way to H and then O. I keep an eye out for the water produced because any odd coefficient placed in front would require a reevaluation for the coefficient in front of the organic compound.

isarose0
Posts: 62
Joined: Fri Sep 28, 2018 12:15 am

Re: Balancing reactions tips

Keep track of each element by creating a small tea chart on the side! You can keep updating the chart when coefficients become higher values

Hannah Yates 1K
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Joined: Fri Sep 28, 2018 12:27 am

Re: Balancing reactions tips

I don’t know if this will help anyone, but every time I balance a combustion reaction, I am always thinking in even numbers. The reason for this is that if there is an odd number of oxygen on the product side of the reaction, the coefficient will end up being a number and a half. If I am always thinking in terms of even numbers, I tend to end with the correct coefficients for O2 (which I find to be the hardest element to balance.)

Chem_Mod
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Re: Balancing reactions tips

I have not read all of the comments, but since there are a lot, I will say a couple of things. First, there is no definitive way to balance equations, it is essentially managed guessing and checking, so don't feel like you're missing something if you don't know "THE" way to do it. There are some good suggestions above. Generally, don't balance hydrogen and oxygen first. Balance the element that is in the least number of species overall first. Try to alter the biggest species the least (meaning don't go to that first for balancing), since changing that coefficient will change the numbers of many different elements. Also, remember that solids like P4 and diatomics like O2 are really nice for balancing, so use those at the end!

Veronica Soliman 4H
Posts: 51
Joined: Fri Sep 28, 2018 12:28 am

Re: Balancing reactions tips

One important tip that my TA actually spoke about was if you keep going back and forth while balancing reactions, it's probably wrong and it's best to attempt that problem from the start.

SophiaKohlhoff4B
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

Re: Balancing reactions tips

I have found it is easiest to balance the least occurring elements first, starting in compounds consisting of the most elements. Then, I leave compounds such as O2 for last because it is easy to balance the lone element of oxygen according to what the rest of the equation calls for.

Nawaphan Watanasirisuk 3B
Posts: 58
Joined: Tue Nov 28, 2017 3:03 am

Re: Balancing reactions tips

I find it helpful, especially when balancing equations with many different elements, to keep track of the amount of each element on the side. It might be a bit tedious if you have to update them each time you change the amount in the equation but usually it works well for me.