I am a beginner in chemistry, please help?

Question

why does aqueous sliver nitrate reacts with aqueous sodium chloride? Why does this reaction occur?

Answer 1

At one level, we can write the reaction like this.  But it isn't very satisfying because the reactants actually exist as a collection of ions.

AgNO3(aq) + NaCl(aq) --> AgCl(s) + NaNO3(aq)

Therefore the ionic equation is more descriptive:

Ag+ + NO3- + Na+ + Cl- -->  AgCl(s) + Na+ + NO3-

This tells us that as the four ions move about in solution, that when a silver ion and a chloride ion collide with an energy equal to or greater than the activation energy that the two will form a bond to eventually form solid silver chloride.

As you can see the sodium and nitrate ions don't do anything, and these are referred to as "spectator ions".  The bottom line is that any time silver ions and chloride ions come in contact solid silver chloride will be produced.

Ag+ +  Cl-  -->  AgCl(s)

And why does solid silver chloride form?  There are two competing forces for ionic compounds in aqueous solution.  One is the lattice energy.  The other is the hydration energy.  The former is the energy that holds the silver and chlorine together in a rigid, crystalline arrangement.  The second is the force that polar water molecules exerts on the Ag and Cl.  In the case of AgCl the force exerted by the water molecules is not large enough to overcome the forces that hold the Ag and Cl together, so that once formed, AgCl cannot dissolve in water.

Answer 2

both r ionic compounds.in solution they exist in ionic form.double displacement reaction takes place in such a way that cations reactv with anions.

AgNO3   +   NaCl   ---------------->  AgCl  +   NaNO3

Answer 3

Try this site, it helped me and all of the aqueous reactions are here.

http://jchemed.chem.wisc.edu/jcesoft/CCA...