Editing Double Replacement Rxn - Neutralization Rxn
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As you know, one of three products (form a solid, water or gas) must be produced in a double chemical reaction for the reaction to occur. Here, we will explain formation of one of these products: <b>the formation of water</b>. As with all double replacement reactions, you have two reactants that are aqueous (compounds that break-up into their ions in water). In other words, you have a bucket of ions before the reaction occurs. The task is to rearrange the ions into new compounds (cpds) knowing that <i>like charged ions can't create cpds.</i> Even though water (H<sub>2</sub>O) is a molecular cpd, we often think of it as made up of two ions, hydronium ion (H<sup>+1</sup>) and hydroxide ion (OH<sup>-1</sup>). It would look like HOH if written as a cpd. Therefore, one of our reactants must contain the hydroxide ion (OH<sup>-1</sup>) and one must contain the hydronium ion (H<sup>+1</sup>). If you place these two reactants into a bucket, you product water (H<sub>2</sub>O). <b>See example below.</b> These types of reactions are very common place to the point that we give the reactants and chemical reaction special names: *Acid - a compound that breaks up into ions in water where one of the ions is hydronium ion (H<sup>+1</sup>). Acids look like ionic cpd that has H as the cation. <b>Example#1</b>, HNO<sub>3</sub> breaks up into 1 H<sup>+1</sup> and 1 NO<sub>3</sub><sup>-1</sup>. <b>Example#2</b>, H<sub>2</sub>SO<sub>4</sub> breaks up into 2 H<sup>+1</sup> and 1 SO<sub>4</sub><sup>-2</sup>. *Base - a compound that breaks up into ions in water where one of the ions is the hydroxide ion (OH<sup>-1</sup>). *Neutralization Rxn - a double replacement reaction that produces water (H<sub>2</sub>O) as one of its products. The two reactants are an acid & a base. *<b>Examples of Neutralization Reaction</b> **1 <nowiki>NaOH</nowiki><sub>(aq)</sub> + 1 HCl<sub>(aq)</sub> ==> 1 H<sub>2</sub>O<sub>(l)</sub> (or 1 HOH<sub>(l)</sub>) + <nowiki>NaCl</nowiki><sub>(aq)</sub> **1 <nowiki>Ca(OH)</nowiki><sub>2 (aq)</sub> + 2 HCl<sub>(aq)</sub> ==> 2 H<sub>2</sub>O<sub>(l)</sub> (or 2 HOH<sub>(l)</sub>) + <nowiki>CaCl</nowiki><sub>2 (aq)</sub> <b>Net Ionic Reaction for Neutralization Reactions</b> To determine any Net Ionic Reaction, you must follow the directions stated in (NetIonicReactions). *<b>Example of Determining Net Ionic Reactions for Neutralization Reaction</b> *Step 1: 1 <nowiki>Ca(OH)</nowiki><sub>2 (aq)</sub> + 2 HCl<sub>(aq)</sub> ==> 2 H<sub>2</sub>O<sub>(l)</sub> + <nowiki>CaCl</nowiki><sub>2 (aq)</sub> '''(Balanced Molecular Equation)''' *Step2 : 1 Ca<sup>+2</sup> + 2 OH<sup>+1</sup> + 2 H<sup>+1</sup> + 2 Cl<sup>-1</sup> --> 2 H<sub>2</sub>O<sub>(l)</sub> + 1 Ca<sup>+2</sup> + 2 Cl<sup>-1</sup> *Step 3: I can't show on this webpage cancel out of spectator ions. You can do it right on work above. The spectator ions are Ca<sup>+2</sup> and 2 Cl<sup>-1</sup> since they are the same on both side of arrow. *Step 4: 2 OH<sup>-1</sup> + 2 H<sup>+1</sup> --> 2 H<sub>2</sub>O<sub>(l)</sub> **But you can cancel out a "2" in each of the coefficient so the actual Net Ionic Reaction is **1 OH<sup>-1</sup> + 1 H<sup>+1</sup> --> 1 H<sub>2</sub>O<sub>(l)</sub> <b>(The Special Condition for Net Ionic Reactions of Neutralization is that all neutralization reactions have the same Net Ionic Reaction: the one above)</b>
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