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### Balancing Equation

Posted: **Sun Apr 15, 2018 11:14 pm**

by **VindyMurthy**

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?

### Re: Balancing Equation

Posted: **Sun Apr 15, 2018 11:19 pm**

by **ElizabethP1L**

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 :)

### Re: Balancing Equation

Posted: **Sun Apr 15, 2018 11:52 pm**

by **105012653 1F**

Is there a trick in doing them faster?

### Re: Balancing Equation

Posted: **Wed Apr 18, 2018 9:36 pm**

by **Komal Prakash 1H**

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

### Re: Balancing Equation

Posted: **Thu Apr 19, 2018 11:16 am**

by **Neha Divi 1K**

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.

### Re: Balancing Equation

Posted: **Fri Apr 20, 2018 11:31 am**

by **AnnaYan_1l**

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

### Re: Balancing Equation

Posted: **Sun Apr 22, 2018 3:07 pm**

by **Eugene Chung 3F**

The matrix method helped me a lot in balancing equations!

### Re: Balancing Equation

Posted: **Fri Sep 28, 2018 1:06 pm**

by **Ashley Kim**

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!