Balancing Equation

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VindyMurthy
Posts: 9
Joined: Fri Apr 06, 2018 11:04 am

Balancing Equation

Postby VindyMurthy » Sun Apr 15, 2018 11:14 pm

Does anyone have any tips for balancing chemical equations in which the coefficients just seem to keep getting higher and whenever one element is balanced, it becomes unbalanced as you try balancing the next element?

ElizabethP1L
Posts: 59
Joined: Wed Nov 15, 2017 3:01 am

Re: Balancing Equation

Postby ElizabethP1L » Sun Apr 15, 2018 11:19 pm

Well, in general, it's important to remember the basic rules and start balancing the least abundant element in a chemical equation to avoid this problem. If you still encounter it, however, you should just use a fraction to balance it temporarily. For example, let's say you need 19 Fe, but that means you will have to change many stoichiometric coefficients to even higher numbers. Then, you should use 19/2 Fe and then multiply the entire equation by 2 to get rid of the fraction and obtain the correct stoichiometric coefficients for the rest of the compounds/elements. Hope this helped :)

105012653 1F
Posts: 30
Joined: Fri Apr 06, 2018 11:02 am

Re: Balancing Equation

Postby 105012653 1F » Sun Apr 15, 2018 11:52 pm

Is there a trick in doing them faster?

Komal Prakash 1H
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Joined: Fri Apr 06, 2018 11:04 am
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Re: Balancing Equation

Postby Komal Prakash 1H » Wed Apr 18, 2018 9:36 pm

If the balancing question is not easy enough to just guess and check then you can use a method where you assign a variable to each unknown coefficient and then make a system of equations for how many times each element appears and solve the system.
For example, in __a_KClO3+__b_C6H12O6+__c__KCl+__d___CO2+__e__H20
K: 1a+0b=1c+0d+0e==>a=c
Cl: 1a+0b=1c+0d+0e==>a=c
O: 3a+6b=2d+e
C: 6b=d
H: 6b=e

You then assume that one variable=1 (in this case, lets make a=1) because there are more variables than equations. Then solve the system of equations.
You get: a=1, b=1/4, c=1, d=6/4, e=6/4, but because you cannot have fractions you multiply by a number that would get rid of all fractions which in this case is 4.
So the final is, a=4, b=1, c=4, d=6, e=6

Neha Divi 1K
Posts: 31
Joined: Fri Apr 06, 2018 11:02 am

Re: Balancing Equation

Postby Neha Divi 1K » Thu Apr 19, 2018 11:16 am

Personally, I like to look for the element that is present the least on both sides as a starting point. From there I try to start with the elements that have smaller quantities present on both sides of the reaction. In addition, like the example Dr. Lavelle used in class I will utilize fractions and multiply them to make it easier in the end.

AnnaYan_1l
Posts: 96
Joined: Fri Apr 06, 2018 11:05 am
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Re: Balancing Equation

Postby AnnaYan_1l » Fri Apr 20, 2018 11:31 am

I really like Komal's method! I tried to do something similar on Test 1.

Eugene Chung 3F
Posts: 142
Joined: Wed Nov 15, 2017 3:03 am

Re: Balancing Equation

Postby Eugene Chung 3F » Sun Apr 22, 2018 3:07 pm

The matrix method helped me a lot in balancing equations!
Image

Ashley Kim
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Joined: Fri Sep 28, 2018 12:19 am
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Re: Balancing Equation

Postby Ashley Kim » Fri Sep 28, 2018 1:06 pm

Other than beginning with the least abundant element and using inspection, you can also try the proportions method. This is similar to the matrix method, where you put variables to represent each coefficient in the equation. Then, you solve it like a mathematical equation with multiple variables. Hope this helped!


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