wiki/education/chemistry/1.html

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<h3><span style="font-family:Arial, Helvetica, sans-serif;">Bohr model (1913)</span></h3>
<figure class="table">
  <table>
    <tbody>
      <tr>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;">Particle</span></td>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;">Symbol</span></td>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;">Relative Charge</span></td>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;">Mass Unit</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Electron</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">e-</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">-1</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">5.4858 x 10<sup>-4</sup></span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Proton</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">p+</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">+1</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">1.0073</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Neutron</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">n</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">0</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">1.0073</span></td>
      </tr>
    </tbody>
  </table>
</figure>
<p>&nbsp;</p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Protons = Electrons ⇒ Atom. Neutral.</span></p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Protons ≠ Electrons ⇒ Ion. Charged.</span></p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Electrons are surrounding the nucleus, consisting of protons and neutrons.</span></p>
<p>&nbsp;</p>
<h3><span style="font-family:Arial, Helvetica, sans-serif;">Element</span></h3>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Mass number are the number of protons and neutrons in the nucleus.</span></p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Atomic number are the number of protons in nucleus.</span></p>
<p>&nbsp;</p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">For example, <sup>4</sup><sub>2</sub>He, where mass number is written on top left, and atomic number on bottom left.</span></p>
<p>&nbsp;</p>
<h3><span style="font-family:Arial, Helvetica, sans-serif;">Periodic Table</span></h3>
<p><span style="font-family:Arial, Helvetica, sans-serif;">The elements are arranged in the order of increasing atomic number, from left to right, from up to down.</span></p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">Each element has a unique atomic number (or the number of proton).</span></p>
<p>&nbsp;</p>
<h3><span style="font-family:Arial, Helvetica, sans-serif;">Electronic arrangement</span></h3>
<p><span style="font-family:Arial, Helvetica, sans-serif;">The maximum number of electron that a shell can hold is 2(n)<sup>2</sup></span></p>
<p><span style="font-family:Arial, Helvetica, sans-serif;">For example, Cl-17,&nbsp;instead of written 2, 8, 7, we can write more clearly with 2, 2+6, 2+5, that is 1s<sup>2</sup> 2s<sup>2</sup> 2p<sup>6</sup> 3s<sup>2</sup> 3p<sup>5</sup></span></p>
<p>&nbsp;</p>
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      <tr>
        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>N</strong></span></td>
        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Max e-</strong></span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">1</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">2</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">2</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">8</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">3</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">18</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">4</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">32</span></td>
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    </tbody>
  </table>
</figure>
<p>&nbsp;</p>
<h3><span style="font-family:Arial, Helvetica, sans-serif;">Electronic configuration</span></h3>
<p><span style="font-family:Arial, Helvetica, sans-serif;">There are subshells inside the shell.</span></p>
<p>&nbsp;</p>
<figure class="table">
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        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Subshell</strong></span></td>
        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Orbitals</strong></span></td>
        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Max e-</strong></span></td>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Name of orbital</strong></span></td>
        <td style="text-align:center;width:200px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Historical Name</strong></span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">s</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">1</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">2</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">s</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Sharp</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">p</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">3</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">6</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">p<sub>x</sub>, p<sub>y</sub>, p<sub>z</sub></span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Principal</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">d</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">5</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">10</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">d<sub>xy</sub>, d<sub>xz</sub>, d<sub>yz</sub>, d<sub>x<sup>2</sup>-y<sup>2</sup></sub>, d<sub>z<sup>2</sup></sub></span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Diffuse</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">f</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">7</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">14</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">&nbsp;</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Fundamental</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">g</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">9</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">18</span></td>
        <td style="text-align:center;">&nbsp;</td>
        <td style="text-align:center;">&nbsp;</td>
      </tr>
    </tbody>
  </table>
</figure>
<p>&nbsp;</p>
<figure class="table">
  <table>
    <tbody>
      <tr>
        <td style="text-align:center;width:100px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Orbitals</strong></span></td>
        <td style="text-align:center;width:300px;"><span style="font-family:Arial, Helvetica, sans-serif;"><strong>Quantum Number</strong></span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">n</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">&nbsp;Principal</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">l</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Angular Momentum</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">m</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Magnetic</span></td>
      </tr>
      <tr>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">s</span></td>
        <td style="text-align:center;"><span style="font-family:Arial, Helvetica, sans-serif;">Spin</span></td>
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    </tbody>
  </table>
</figure>
<p>&nbsp;</p>