What are the coefficients for the reaction _cl2o5 + _h2o → _hclo3 once it is balanced?

_Cl2O5 + _H2O → _HClO3

From the H2O, we see that HCLO3 will have to have a multiple of 2 in front, since we only get delivered an even number of oxygen atoms:

_Cl2O5 + _H2O → 2HClO3

Now, on the right side side we have 2 H atoms (same as on the left side), 2 Cl atoms (again, the same) and  6(2*3) oxygen atoms (again the same: 5 from the first part and one from the second.

So this is already our solution:

Cl2O5 + H2O → 2HClO3

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