# How to write equations for a reaction of metals with water

Please write two equations for reacting lithium with water and barium with water. Make sure to add the states of matter after each compound.

Currently, for lithium I have the equation

$$\ce{2Li(s) + 2H2O(l) -> 2LiOH(aq) + H2(g)}$$

I have not attempted the second one yet.

• Considering that $\ce{LiOH}$ is a strong base, the $\ce{Li}$ would become an ion since it is a strong base. – Asker123 Apr 14 '15 at 1:51
• I'm pretty sure you are correct. (lenntech.com/periodic/water/lithium/lithium-and-water.htm). You should have confidence and do your homework with confidence. The Barium reaction is very similar and you should be able to do it. – Andy Apr 14 '15 at 1:59
• Looks fine to me as well, as @Andy says, you should be able to approach the second one (similar to your previous post chemistry.stackexchange.com/questions/28646/…) - but keep what Asker123 stated in mind. – user15489 Apr 14 '15 at 2:02

With all technicalities aside, your first equation is on par. The second one should be adjusted a bit for that +2 charge. It is as follows:

$$\ce{Ba(s) + 2HOH(l) -> Ba(OH)2(aq) + H2(g)}$$

NOTE: If need be, you must also take into account the fact that two strong bases are being generated. SO if you wish you might as well dissociate the Barium Hydroxide and the Lithium Hydroxide as well.

Thanks. Correct me if I am wrong.

• Wouldn't Hydrogen be produced as a gas as well? A small quantity may remain dissolved but I would think that if any sizable amount of Barium is added, hydrogen gas would be produced since the solubility of hydrogen gas is quite low under standard conditions in water. – Andy Apr 14 '15 at 2:22

If the reactants are a metal and water, the products would be a base and hydrogen gas (don't forget the subscript 2 for diatomic).

$$\ce{2Li(s) + 2H2O(l) -> 2LiOH(aq) + H2(g)}$$

Also remember that if the metal that displaces the Hydrogen has a charge, for instance Iron (II), although that wouldn't be realistic, the reactants would become $\ce{Fe(OH)2 + H2}$.

Whenever the reactants are a non-metal oxide + water, an acid forms.