<h2>The Nucleus</h2>
<p>Unlike the electron, the nucleus <strong>can</strong> be broken up into smaller <a data-lesson="atoms-and-compounds" data-subject="chemistry" data-tutorial="chemistry-essential-ideas" href="https://app.ulearngo.com/chemistry/chemistry-essential-ideas/atoms-and-compounds">building</a> blocks called <strong>protons</strong> and <strong>neutrons</strong>. Together, the protons and neutrons are called <strong>nucleons</strong>.</p>
<div class="ns-school-defn2">
<h3>Did You Know?</h3>
<p>Scientists believe that the electron can be treated as a <strong>point particle</strong> or <strong>elementary particle</strong> meaning that it cannot be broken down into anything smaller.</p>
</div>
<section>
<h2 class="title">The Proton</h2>
<p>The electron carries one unit of <strong>negative</strong> electric charge (i.e. \(-\text{1.6} \times \text{10}^{-\text{19}}\) \(\text{C}\), C is Coulombs).</p>
<p>Each proton carries one unit of <strong>positive</strong> electric charge (i.e. \(\text{+1.6} \times \text{10}^{-\text{19}}\) \(\text{C}\)). Since we know that atoms are <strong>electrically neutral</strong>, i.e. do not carry any extra charge, then the number of protons in an atom has to be the same as the number of electrons to balance out the positive and negative charge to zero. The total positive charge of a nucleus is equal to the number of protons in the nucleus. The proton is much heavier than the electron (\(\text{10 000}\) times heavier!) and has a mass of \(\text{1.6726} \times \text{10}^{-\text{27}}\) \(\text{kg}\). When we talk about the <a data-lesson="atomic-mass" data-subject="chemistry" data-tutorial="atoms-molecules-ions" href="https://app.ulearngo.com/chemistry/atoms-molecules-ions/atomic-mass">atomic mass</a> of an atom, we are mostly referring to the combined mass of the protons and neutrons, i.e. the nucleons.</p>
</section>
<section>
<h2 class="title">The Neutron</h2>
<p>The neutron is electrically neutral i.e. it carries no charge at all. Like the proton, it is much heavier than the electron and its mass is \(\text{1.6749} \times \text{10}^{-\text{27}}\) \(\text{kg}\) (slightly heavier than the proton).</p>
<h3>Table: Summary of the Particles Inside the Atom</h3>
<div>
<table summary="                ">
<tbody>
<tr>
<td> </td>
<td>
<p><strong>proton</strong></p>
</td>
<td>
<p><strong>neutron</strong></p>
</td>
<td>
<p><strong>electron</strong></p>
</td>
</tr>
<tr>
<td>
<p><strong>Mass (\(\text{kg}\))</strong></p>
</td>
<td>
<p>\(\text{1.6726} \times \text{10}^{-\text{27}}\)</p>
</td>
<td>
<p>\(\text{1.6749} \times \text{10}^{-\text{27}}\)</p>
</td>
<td>
<p>\(\text{9.11} \times \text{10}^{-\text{31}}\)</p>
</td>
</tr>
<tr>
<td>
<p><strong>Units of charge</strong></p>
</td>
<td>
<p>\(\text{+1}\)</p>
</td>
<td>
<p>\(\text{0}\)</p>
</td>
<td>
<p>\(-\text{1}\)</p>
</td>
</tr>
<tr>
<td>
<p><strong>Charge (\(\text{C}\))</strong></p>
</td>
<td>
<p>\(\text{1.6} \times \text{10}^{-\text{19}}\)</p>
</td>
<td>
<p>\(\text{0}\)</p>
</td>
<td>
<p>\(-\text{1.6} \times \text{10}^{-\text{19}}\)</p>
</td>
</tr>
</tbody>
</table>
</div>
</section>
<section></section>

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The Nucleus

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 the essential ideas in chemistry, including the scientific method, laboratory skills and safety, states of matter, measurement uncertainty, models of the atom, electronic configurations, and more.


The Nucleus

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