Question

Question #b560e

Answer 1

Both equations are balanced correctly.

Explanation:

You first learn when balancing equations you should only use whole numbers. While this is a great way to first learn to balance chemical equations, you don't, in fact, have to only use whole numbers.

The reason why this doesn't violate the law stating you can't have half of a molecule (i.e. one half of an atom of `Na^(+)` and `Cl^(-)` in `NaCl`) is because the numbers in balancing equations are indicating how many moles of the substance you have. You can very well have `1/2` of a mole of something and not violate that law.

Thus, both equations are valid.

It is important to note however, that each method might be used for different reasons.

For instance, when using a mole ratio to find how much product you will make from a limiting reagent, the chemical reaction will be balanced using whole numbers.

However, when calculating values for `DeltaH` in Thermochemistry (using Hess's law, for instance), the fractional balancing is used more often.

I hope this helps!