How do you balance and translate this reaction: #KClO_3(s) -> KCl(s) + O_2(g)#?
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
But we can't have half atoms in chemical equations. Multiply the entire equation by 2 to get rid of the half atom.
Now everything is balanced : There are 2 potassium, 2 chlorine and 6 oxygen atoms.