If something is soluble, it means it's dissolved in liquid. Generally, the compound associate with the liquid (l) phase label is water; everything else takes the (aq) phase. Note that all these phase labels are written as superscripts after the species they are labeling.

All of the three salts will dissolve completely in the solution, resulting in all of the ions interacting with one another.

$\displaystyle Ag_2SO_4\rightarrow 2Ag^++SO_4^{2-}$

$\displaystyle NH_4Cl\rightarrow NH_4^++Cl^-$

$\displaystyle KNO_3\rightarrow K^++NO_3^-$

Chloride compounds are generally soluble, but the salt $\displaystyle AgCl$ is one of the notable insoluble chloride salts. When these two ions meet in solution, they will combine and precipitate out of the solution. All the other ion combinations still form soluble compounds except for $\displaystyle AgSO_4$, which is also insoluble.

The precipitate will be the product that is insoluble in water, so your choices are $\displaystyle AgCl$ or $\displaystyle NaNO_3$.

Nitrate salts are always soluble in water, as are alkali metal salts such as sodium. Thus, we know that $\displaystyle NaNO_3$ will fully dissolve.

Halide salts (such as chlorides) are soluble in water, unless they are combined with silver, lead, or mercury. In this case, the silver atom makes the halide salt, $\displaystyle AgCl$, insoluble in water. $\displaystyle AgCl$ is the precipitate.

The precipitate will be the product that is insoluble in water. The products in this reaction are $\displaystyle BaSO_4$ and $\displaystyle NaCl$.

Halide salts (such as chlorides) are soluble in water, unless combined with silver, lead, or mercury. In this case, $\displaystyle NaCl$ is soluble in water.

Sulfate salts are soluble in water, unless combined with silver, calcium, strontium, barium, or lead ions. In this case, $\displaystyle BaSO_4$ is insoluble and is, therefore, the precipitate.

Water turning to ice is not a chemical reaction, it is a physical reaction. Nothing is changing about the water molecules chemically, they're just going from a liquid state to a solid state. Burning wood is a non-reversible chemical change because the carbon in the wood is reacting with oxygen to create ash and smoke, also, energy in the form of light and heat is released. Rust is formed when iron reacts chemically with oxygen, producing the red-orange color of rust. A gas forming is a good indicator that a chemical reaction has taken place. A precipitate is also a good indicator for a chemical reaction. It may just seem like something is changing states, but the precipitate is not a solid version of one of the reactants, it's the insoluble product formed from the chemical reaction.

If something is insoluble, it means it cannot be dissolved. The phase label reserved for solids is (s). The other phase labels are: (l) = liquid; (aq) = aqueous; (g) = gas; and the (r) phase label does not exist. Note that all of the phase labels are written as subscripts after the species; for example: $\displaystyle H_2O_{(s)}$.

The precipitate will be the product that is insoluble in water, so your choices are $\displaystyle AgCl$ or $\displaystyle NaNO_3$.

Nitrate salts are always soluble in water, as are alkali metal salts such as sodium. Thus, we know that $\displaystyle NaNO_3$ will fully dissolve.

Halide salts (such as chlorides) are soluble in water, unless they are combined with silver, lead, or mercury. In this case, the silver atom makes the halide salt, $\displaystyle AgCl$, insoluble in water. $\displaystyle AgCl$ is the precipitate.

The precipitate will be the product that is insoluble in water, so your choices are $\displaystyle AgCl$ or $\displaystyle NaNO_3$.

Nitrate salts are always soluble in water, as are alkali metal salts such as sodium. Thus, we know that $\displaystyle NaNO_3$ will fully dissolve.

Halide salts (such as chlorides) are soluble in water, unless they are combined with silver, lead, or mercury. In this case, the silver atom makes the halide salt, $\displaystyle AgCl$, insoluble in water. $\displaystyle AgCl$ is the precipitate.