I enjoy this tutorial. It's simple to understand and straight forward to the point.Thanks!

<h2>Dissociation of Sodium Chloride in Water</h2>
<p>It is the <a data-lesson="polar-molecules" data-subject="chemistry" data-tutorial="bonding-atomic-combinations" href="https://app.ulearngo.com/chemistry/bonding-atomic-combinations/polar-molecules">polar</a> nature of water that allows <a data-lesson="ionic-compounds" data-subject="chemistry" data-tutorial="atoms-molecules-ions" href="https://app.ulearngo.com/chemistry/atoms-molecules-ions/ionic-compounds">ionic compounds</a> to dissolve in it. In the case of sodium chloride (\(\text{NaCl}\)) for example, the positive sodium ions (\(\text{Na}^{+}\)) are attracted to the negative pole of the water molecule, while the negative chloride ions (\(\text{Cl}^{-}\)) are attracted to the positive pole of the water molecule. When sodium chloride is dissolved in water, the polar water molecules are able to work their way in between the individual ions in the lattice. The water molecules surround the negative chloride ions and positive sodium ions and pull them away into the solution. This process is called <strong>dissociation</strong>.</p>
<p>Note that the positive <a data-lesson="dissociation-in-water" data-subject="chemistry" data-tutorial="reactions-in-aqueous-solution" href="https://app.ulearngo.com/chemistry/reactions-in-aqueous-solution/dissociation-in-water">side</a> of the water molecule will be attracted to the negative chlorine ion and the negative side of the water molecule to the positive sodium ions. A simplified representation of this is shown in the figure below. We say that dissolution of a substance has occurred when a substance dissociates or dissolves. Dissolving is a <a data-lesson="physical-chemical-properties" data-subject="chemistry" data-tutorial="chemistry-essential-ideas" href="https://app.ulearngo.com/chemistry/chemistry-essential-ideas/physical-chemical-properties">physical</a> <a data-lesson="chemistry-104-summary-1" data-subject="chemistry" data-tutorial="physical-and-chemical-change" href="https://app.ulearngo.com/chemistry/physical-and-chemical-change/chemistry-104-summary-1">change</a> that takes place. It can be reversed by removing (evaporating) the water.</p>
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<h3>Definition: Dissociation</h3>
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<p>Dissociation is a general process in which ionic compounds separate into smaller ions, usually in a <a data-lesson="reversible-reactions" data-subject="chemistry" data-tutorial="chemical-equilibrium" href="https://app.ulearngo.com/chemistry/chemical-equilibrium/reversible-reactions">reversible</a> manner.</p>
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<h3>Definition: Dissolution</h3>
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<p>Dissolution or dissolving is the process where ionic crystals break up into ions in water.</p>
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<h3>Definition: Hydration</h3>
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<p>Hydration is the process where ions become surrounded with water molecules.</p>
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<div class="wp-caption alignnone" style="width: 506px"><img alt="fc1e899be15a0e341f41fd5df21eaa8c.png" height="217" src="https://data.ulearngo.com/assets/2a050789-7108-4d89-9502-7902353c90fd" width="506"/><p class="wp-caption-text">Sodium chloride dissolves in water</p></div>
<p>The dissolution of sodium chloride can be represented by the following equation:</p>
<p>\[\text{NaCl (s)} \rightarrow \text{Na}^{+}\text{(aq)} + \text{Cl}^{-}\text{(aq)}\]</p>
<p>The dissolution of potassium sulfate into potassium and sulfate ions is shown below as another example:</p>
<p>\[\text{K}_{2}\text{SO}_{4}\text{(s)} \rightarrow 2\text{K}^{+}\text{(aq)} + \text{SO}_{4}^{2-}\text{(aq)}\]</p>
<p>Remember that <strong>molecular</strong> substances (e.g. covalent compounds) may also dissolve, but most will not form ions. One example is glucose.</p>
<p>\[\text{C}_{6}\text{H}_{12}\text{O}_{6}\text{(s)} \rightarrow \text{C}_{6}\text{H}_{12}\text{O}_{6}\text{(aq)}\]</p>
<p>There are exceptions to this and some molecular substances <em>will</em> form ions when they dissolve. Hydrogen chloride for example can ionise to form <a data-lesson="hydrogen-reactions" data-subject="chemistry" data-tutorial="metals-metalloids-nonmetals" href="https://app.ulearngo.com/chemistry/metals-metalloids-nonmetals/hydrogen-reactions">hydrogen</a> and chloride ions.</p>
<p>\[\text{HCl (g)} + \text{H}_{2}\text{O (l)} \rightarrow \text{H}_{3}\text{O}^{+}\text{(aq)} + \text{Cl}^{-}\text{(aq)}\]</p>
<p>You can try dissolving ionic compounds such as potassium permanganate, sodium hydroxide and potassium nitrate in water and observing what happens.</p>

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Dissociation of Sodium Chloride in Water

Chemistry generally explores the substances of which matter is composed, the investigation of their properties and reactions, and the use of such reactions to form new substances. 

Chemistry

Explore how different substances dissolve and react with each other in water, including ionization and conductivity, precipitation reactions, tests for anions, and various types of reactions such as redox and ion exchange.


Dissociation of Sodium Chloride in Water

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