Soluble or Insoluble?
Silver carbonate is soluble in concentrated aqueous ammonia (roughly 18 M). The aqueous ammonia can form a coordinate complex that removes free silver ions from the solution, increasing the solubility.
A saturated solution is one in which the concentration of all the solutes is equal, and additional solute would not increase the concentration. The opposite is a dilute solution; this solution can accept more solute.
The solubility of a compound is influenced by the solvent utilized and the temperature of the solution. Some compounds are soluble at room temperature, others are soluble at lower temperatures.
Typically, compounds with alkali metal cations are soluble in water. These cations are often sodium, potassium or calcium.
Ammonium salts can also be soluble in water because of the way the N in ammonia attracts a slightly positive H in an acid. This is called a coordinate bond or dative covalent bond form.
Silver is a transition metal, so it is also poorly soluble in water. When combined with a dilute acid, it decomposes into elemental silver and produces carbon dioxide. This process can be accelerated by heating with an acid. It is also a very light-sensitive compound, so be careful in handling it, and wear proper protection.