Question

How to make chemical formulas, supposing if I have CaO+H2O --> Ca(OH)2 , how did I get this, means why Ca(OH)2 and why not CaOH2 or OH2Ca, please explain everything, I have the problem in basic​​

Answer 1

Explanation:

Its written as Ca(OH)2 because it means CaO2H2. (OH)2 basically means (O×2)+(H×2) which = (OH)2. So writing CaOH2 means you took away 1 Oxygen. Which is wrong.

Now why you can't write OH2Ca because Ca kicks of 2 electron which makes it positive (cation) with +2 charge and OH is negative (anion) with -1 charge so to balance Ca+2 combines with OH-1 hence CaO2H2 or Ca(OH)2 (there is a rule that you have to write cations first)