What if when I find my product, I get the same compound as I did in my reactant? For example, FeCl3 + HCl ->FeCl3 + HCl.
Then something is wrong. In this case, FeCl3 and HCl usually don't react. In very concentrated solutions of HCl, the FeCl4^- or FeCl6^-3 ion can form. In normal circumstances we would write NR after the arrow to indicate there was no reaction.
To determine if a reaction will occur, you can use a set of guidelines known as the activity series or solubility rules. These rules help predict whether a compound will react and form a new compound or remain unchanged. In the case of FeCl3 + HCl, FeCl3 is a compound that is typically soluble in water, while HCl is an acid that dissociates completely in water.
According to the solubility rules, most chlorides (such as FeCl3) are soluble in water, and hydrogen chloride (HCl) is a strong acid that ionizes completely in water. Therefore, when FeCl3 and HCl are combined, a reaction is expected to occur. However, it is important to note that reactions can sometimes be affected by factors such as concentration, temperature, and presence of catalysts.
If you obtained the same compounds in the product as you had in the reactant (FeCl3 + HCl -> FeCl3 + HCl), it suggests that no reaction took place. This could be due to incorrect conditions or other factors preventing the reaction from occurring. In such cases, it is important to review the reaction conditions, check the reactants' properties, and ensure they are capable of undergoing a chemical reaction together.
If you encounter a reaction like this, it is generally best to label it as "no reaction" or "NR" in your equation to indicate that no chemical change occurred between the reactants.