Neutralization reactions occur when an acid and a base react to form salt and water. When we mix an acid and a base, one substance will neutralize the properties of the other, as they chemically react with each other and, therefore, this reaction is called a neutralization reaction.
So here we have:
Acid: Nitric Acid (HNO3)
Base: Calcium hydroxide (Ca(OH)2)
Nitric acid ionizate and forms H+ and NO3^-
Calcium hydroxide dissociate and forms Ca2+ and OH-
H+ with OH- form water - H2O
Ca2+ with NO3^- form a sal - calcium nitrate - Ca(NO3)2
The unbalaced equation is:
HNO3(aq) + Ca(OH)2(aq) -> Ca(NO3)2(aq) + H2O(l)
To balance this equation, as it is an acid and base reaction, there is a trick to balance the reaction faster. We use the quantity of atoms of the cation of the salt on the products side as stoichiometric coefficient of the hydroxide and the quantity of the anion of the salt as stoichiometric coefficient of the acid.
In this case, the salt is: Ca(NO3)2
So we have 1 cation and 2 anions.
So the coefficient of the hydroxide will be 1 and for the acid will be 2:
2 HNO3 + 1 Ca(OH)2 --> __Ca(NO3)2 + __H2O
The coefficient of the salt will be 1 and for the water (H2O) is the coefficient of the acid multiplied by the coefficient of the acid (1x2 = 2):
2 HNO3 + 1 Ca(OH)2 --> 1 Ca(NO3)2 + 2 H2O
Now the equation is balanced.
Answer: 2 HNO3 + 1 Ca(OH)2 --> 1 Ca(NO3)2 + 2 H2O