Writing A Net Ionic Equations

This simple exercise is about how to write a net ionic equation for the precipitation reaction that occurs when making solutions of calcium chloride and sodium carbonate. So, first of all, our task is to write a net ionic equation for the precipitation reaction, given the names of the reactants present in the solution. Then, we write the chemical formulas of the reactants and products, and determine which product is insoluble by using the table of solubility. Next, we write and balance the molecular equation. After that, we write each soluble strong electrolyte as separate ions to obtain the complete ionic equation. Finally, we eliminate these spectator ions to obtain the net ionic equation. So, calcium chloride (CaCl2) is composed of calcium ions and chloride ions. Hence, an aqueous solution of the substance is calcium chloride (CaCl2). As we can see here in the solubility table, the chloride compounds are almost soluble, with the exception of these three compounds. Explanation for sodium carbonate (Na2CO3): It is composed of sodium ions and carbonate ions. In a second solution of the compound, Na2CO3, that also happens to be soluble in water because most carbonates are insoluble. However, with the presence of alkali metal cations, it will become soluble. As we can see in the table, in the molecular equation for precipitation reactions, the anions and calcium carbonate (CaCO3) is formed when calcium ions (Ca2+) react with carbonate ions (CO32-). Similarly, sodium ions (Na+) can exchange with chloride ions (Cl-) to form sodium chloride (NaCl). According to the solubility guidelines in section 4.1, calcium carbonate is insoluble while sodium chloride is soluble. Therefore, the balanced molecular equation is: CaCl2(aq) + Na2CO3(aq) -> CaCO3(s) + 2NaCl(aq) Carbonate. One carbonate, but we have here two sodium and two chloride ions. So, that means we need to add a 2 in front of this. In that way, it will affect the sodium and also the chloride. If we put a 2 here, it's going to be a totally different compound, NaCl. And by the way, that doesn't exist. Ok and Na2Cl2, that doesn't exist either. So, you need to add coefficients to balance the equation. Remember that you need to just add coefficients at the beginning or in front of each of the compounds of a molecular equation. Ok, so we need to add that coefficient in front of any of the compounds that need to change the number of items to balance the equation. So, in a complete ionic equation, only the strong electrolytes, such as soluble sodium carbonate, sodium ions, and chloride ions, will be shown. Ionic compounds are written as separate ions. For example, calcium chloride dissociates into calcium and chloride ions. Similarly, sodium carbonate dissociates into sodium and carbonate ions. All of these ions are dissolved in the solution because they are all electrolytes. However, calcium carbonate is a different case as it is insoluble. As a result, we do not include it in the equation as component ions. The complete equation would look something like this: CaCl2 (s) -> Ca2+ (aq) + 2Cl- (aq) Na2CO3 (s) -> 2Na+ (aq) + CO32- (aq) Sodium ions in Aitkin solution, plus the carbonate ion in a key solution, react to form calcium carbonate, which is insoluble. We want to keep it that way, so we can't associate it. On the other hand, sodium chloride is a soluble compound in water, so we separate it with association. Additionally, we have two sodium ions and two chloride ions that need to be balanced before canceling. The spectator ions are sodium and chloride, which are present in both the reactants and the products. Therefore, we need to cancel them to obtain the net ionic equation. The net ionic equation is as follows: [Ca^{2+}(aq) + CO3^{2-}(aq) \rightarrow CaCO3(s)] Is the net ionic equation, so we can check our results by confirming that both the elements and the electric charge are balanced. Each side has one calcium and one carbonate. When carbonate, the net charge on each side is zero. Here, we don't have any charge, so we have a net charge of zero in the product. We have a +2 charge on one side, but also a -2 charge, so +2 and -2 equal zero. Therefore, we also have a net charge of zero on both sides. This means that we have a balance in electric charges. If none of the ions in the ionic equation are removed from solution or change in some way, all ions are spectator ions and no reaction occurs. Sometimes, it could happen that the possible products that you. Would produce are also soluble, so that means that you can have a precipitation reaction. Okay, so a reaction does not occur in that case if you eliminate all of them. That's just if none of the product is soluble.