Balancing Equations: Nitrogen Dioxide + Water = Nitric Acid

[recon]

Hi,

I've always had trouble balancing equations. Does anyone know if there is an 'algorithm' for balancing equations? For example, how do I balance

"Nitrogen Dioxide + Water = Nitric Acid"-Sorry, don't know how to use Latex!

Any help will be greatly welcomed.

 

[ShawnD]

What I always do is balance things in this order:
1. complex ions
2. atoms with relatively low numbers
3. atoms with high numbers

Here is what you wanted balanced (I think)

$$NO_2 + H_2O \rightarrow HNO_3$$

This equation by itself cannot be balanced. The nitrogens balance, the oxygens balance, but the hydrogens do not balance. Trying to balance the hydrogens makes the problem bigger.

The reason it cannot be done is because that equation is not correct. The real reaction that happens is:
nitrogen dioxide + water + oxygen = nitric acid

$$NO_2 + H_2O + O_2 \rightarrow HNO_3$$ (unbalanced)

Here is balanced:

$$4NO_2 + 2H_2O + O_2 \rightarrow 4HNO_3$$

This is a strange reaction that my method doesn't work too well on. I started by balancing hydrogens, then nitrogens, then oxygen.

 

[ravenprp]

Hi there,

Balancing equations can definitely be tricky, but there are a few steps you can follow to make it easier. First, you want to make sure that the number of atoms of each element is the same on both sides of the equation. In this case, we have 1 nitrogen atom and 2 oxygen atoms on the left side of the equation, and 1 nitrogen atom, 3 oxygen atoms, and 1 hydrogen atom on the right side.

To balance the nitrogen atoms, we can add a coefficient of 2 in front of the nitric acid to make it 2NO3H. This gives us 2 nitrogen atoms on both sides. Next, we can add a coefficient of 2 in front of the water to make it 2H2O. This gives us 4 hydrogen atoms on the right side, so we need to add a coefficient of 2 in front of the nitrogen dioxide to balance the hydrogen atoms. This gives us 4 hydrogen atoms on both sides.

Now, we have 2 nitrogen atoms and 4 oxygen atoms on both sides, but we still have an extra oxygen atom on the left side. To balance this, we can add a coefficient of 2 in front of the nitrogen dioxide, giving us 2NO2. This gives us 4 oxygen atoms on both sides, and our equation is now balanced: 2NO2 + 2H2O = 2NO3H.

I hope this helps! Just remember to start by balancing the elements that appear in only one compound, and then work your way through the rest of the elements. Good luck!