How do you balance and translate this reaction: KClO_3(s) -> KCl(s) + O_2(g)?

May 23, 2017

$2 K C l {O}_{3} \left(s\right) \rightarrow K C l \left(s\right) + 3 {O}_{2} \left(g\right)$

Explanation:

Let's identify : K is potassium, Cl is chlorine and O is oxygen.

Let's identify the state symbols : (s) is solid, and (g) is gas.

Let's identify the unbalanced element(s) : Potassium is balanced, there are 1 on each side. Chlorine is balanced, there are 1 on each side. Oxygen is not balanced, there's 3 on the LHS, and 2 on the RHS.

How many times does 2 go into 3? The answer is 1.5. Change the coefficient of the oxygen on the RHS from 1 to 1.5

$K C l {O}_{3} \left(s\right) \rightarrow K C l \left(s\right) + 1.5 {O}_{2} \left(g\right)$

But we can't have half atoms in chemical equations. Multiply the entire equation by 2 to get rid of the half atom.

$2 K C l {O}_{3} \left(s\right) \rightarrow 2 K C l \left(s\right) + 3 {O}_{2} \left(g\right)$

Now everything is balanced : There are 2 potassium, 2 chlorine and 6 oxygen atoms.