How do you know what compounds or elements are produced when potassium comes in contact with water? ?
Saturday, August 7th, 2010 at
5:38 AM
also..does anyone know how to balance an equation like this?
Filed under: Water
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K is an alkali metal, so imagine water acting as an acid. Then you get the general equation, acid + metal = hydrogen + salt
H2O + K ? H2 + KOH, where a hydroxide is a salt of water.
Now you need to balance. 2H2O + 2K ? H2 + 2KOH
Potassium is an alkalai metal, very easy to oxidize because it has a relatively high energy electron. So the metal K(s) oxidizes to K+. In water, this will reduce an H+ to H(dot). Two of these will give you a hydrogen molecule. The resulting hydroxide ions balance the potassium ions. So the equation is:
2 K(s) + 2 H2O -> 2 KOH + H2
Hm..Potassium is K, water’s H2O. I think it would be a single displacement reaction, and the potassium and hydrogen would switch, since potassium is higher in activity. So…hydrogen and potassium oxide I’m pretty sure? Which would be H2 + K2O.
And IF that’s right, you go…2K + H2O arrow H2 + K2O
Maybe. Just maybe.
The molecules of water are composed of 2 H and 1 O. Naturally, a K atom which as a +1 charge will react with a hydroxide ion (OH) with a charge -1, breaking the water molecule and forming potassium hydroxide (KOH) and molecular hydrogen along with a large amount of heat. The heat causes a reaction between the released hydrogen and oxygen in the atmosphere producing a flame. The equation looks like this:
K?+2H?O -> 2KOH+H?