How would you balance: Na + H2O --> NaOH + H2?

2 Answers
Nov 16, 2015

2Na+2H2O2NaOH+H2

Explanation:

You have to count the number of atoms in both sides of the reaction to be equal, to make it a little easier you can make a list. So in the equation Na+H2ONaOH+H2, there are
1Na1
2H3
1O1
So you multiply NaOH and H2O by 2, so you have 4 hydrogens in both sides, and then multiply Na by 2 to be equal to the NaOH you previously multiplied.

Nov 12, 2016

2Na(s)+2H2O(l)2NaOH(aq)+H2(g)

Explanation:

I'm assuming that you're supposed to balance this chemical equation by inspection. You could also balance it by using oxidation numbers, but I don't think that you're supposed to go that route here.

So, your unbalanced chemical equation looks like this

Na(s)+H2O(l)NaOH(aq)+H2(g)

Notice that you have 3 atoms of hydrogen on the products' side, but only 2 on the reactants' side.

Here is where a little experience can come in handy. You can multiply the sodium hydroxide by 2 to get a total of 4 atoms of hydrogen on the products' side.

This will allow you to simply double the number of water molecules to get 4 atoms of hydrogen on the reactants' side.

So you now have

Na(s)+2H2O(l)2NaOH(aq)+H2(g)

Balance the atoms of sodium by multiplying sodium metal by 2

2Na(s)+2H2O(l)2NaOH(aq)+H2(g)

And now check to see if the atoms of oxygen are balanced. You have 2 atoms of hydrogen on the reactants' side and 2 on the products' side, which means that the equation is balanced.