<section>
<h2 class="title">Chemical properties of the groups</h2>
In some groups, the <a data-lesson="elements" data-subject="chemistry" data-tutorial="classification-of-matter" href="https://app.ulearngo.com/chemistry/classification-of-matter/elements">elements</a> display very similar chemical properties and some of the groups are even given special names to identify them. The characteristics of each group are mostly determined by the electron configuration of the <a data-lesson="chemical-formulas" data-subject="chemistry" data-tutorial="atoms-molecules-ions" href="https://app.ulearngo.com/chemistry/atoms-molecules-ions/chemical-formulas">atoms</a> of the elements in the group. The names of the groups are summarized in the figure below.
<img alt="e371af75ced8df9734706c394c9e7166.png" src="https://data.ulearngo.com/assets/a4793c8f-19fb-41b6-9f53-56ce3cb4de0d"/>
Groups on the periodic table
A few points to note about the groups are:
<ul>
<li>
Although <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> appears in group 1, it is not an alkali metal.
</li>
<li>
Group 15 elements are sometimes called the pnictogens.
</li>
<li>
Group 16 elements are sometimes known as the chalcogens.
</li>
<li>
The halogens and the alkali metals are very reactive groups.
</li>
<li>
The noble gases are inert (unreactive).
</li>
</ul>
<h3>Optional Video: Groups of the Periodic Table</h3>
<div class="note visit"><iframe allowfullscreen="allowfullscreen" frameborder="0" height="360" src="https://www.youtube.com/embed/LDHg7Vgzses?rel=0&amp;modestbranding=1&amp;cc_lang_pref=en&amp;cc_load_policy=1" width="640"></iframe></div>
The following diagram illustrates some of the key trends in the groups of the periodic table:
<div class="wp-caption alignnone" style="width: 949px"><img alt="7350fca6e822799bfebf8f284e91d2f0.png" height="394" src="https://data.ulearngo.com/assets/c847194a-63d0-48c3-8f20-954a7b8b8440" width="949"/>Trends in the groups on the periodic table.</div>
The table below summarises the patterns or trends in the properties of the elements in group 1. Similar trends are observed for the elements in the other groups of the periodic table. We can use the information in the table below to predict the chemical properties of unfamiliar elements. For example, given the element Francium (\(\text{Fr}\)) we can say that its electronic structure will be \([\text{Rn}]7\text{s}^1\), it will have a lower first ionisation energy than caesium (\(\text{Cs}\)).
One general trend that is not shown is the melting and boiling points. For the <a data-lesson="metals" data-subject="chemistry" data-tutorial="classification-of-matter" href="https://app.ulearngo.com/chemistry/classification-of-matter/metals">metals</a> (groups 1 to 13) the melting and <a data-lesson="boiling-points" data-subject="chemistry" data-tutorial="liquids-and-solids" href="https://app.ulearngo.com/chemistry/liquids-and-solids/boiling-points">boiling points</a> increase as you go up the group. For the <a data-lesson="non-metals" data-subject="chemistry" data-tutorial="classification-of-matter" href="https://app.ulearngo.com/chemistry/classification-of-matter/non-metals">non-metals</a> the melting and boling points decrease as you go up the group.
You should also recall that the metals are found on the left of the periodic table, non-metals are on the right and <a data-lesson="metalloids" data-subject="chemistry" data-tutorial="classification-of-matter" href="https://app.ulearngo.com/chemistry/classification-of-matter/metalloids">metalloids</a> are found on the zig-zag line that starts at boron.
<div>
<table summary=" ">
<tbody>
<tr>
<td>
Element
</td>
<td>
\(_{3}^{7}\text{Li}\)
</td>
<td>
\(_{11}^{23}\text{Na}\)
</td>
<td>
\(_{19}^{39}\text{K}\)
</td>
<td>
\(_{37}^{86}\text{Rb}\)
</td>
<td>
\(_{55}^{133}\text{Cs}\)
</td>
</tr>
<tr>
<td>
Electron structure
</td>
<td>
\([\text{He}]2\text{s}^1\)
</td>
<td>
\([\text{Ne}]3\text{s}^1\)
</td>
<td>
\([\text{Ar}]4\text{s}^1\)
</td>
<td>
\([\text{Kr}]4\text{s}^1\)
</td>
<td>
\([\text{Xe}]5\text{s}^1\)
</td>
</tr>
<tr>
<td rowspan="2">
Group 1 chlorides
</td>
<td>
\(\text{LiCl}\)
</td>
<td>
\(\text{NaCl}\)
</td>
<td>
\(\text{KCl}\)
</td>
<td>
\(\text{RbCl}\)
</td>
<td>
\(\text{CsCl}\)
</td>
</tr>
<tr>
<td colspan="5">
Group 1 elements all form <a data-lesson="naming-alkyl-halides" data-subject="chemistry" data-tutorial="organic-molecules" href="https://app.ulearngo.com/chemistry/organic-molecules/naming-alkyl-halides">halogen</a> <a data-lesson="compounds-2" data-subject="chemistry" data-tutorial="quantitative-aspects-chemical-change" href="https://app.ulearngo.com/chemistry/quantitative-aspects-chemical-change/compounds-2">compounds</a> in a 1:1 ratio
</td>
</tr>
<tr>
<td rowspan="2">
Group 1 oxides
</td>
<td>
\(\text{Li}_{2}\text{O}\)
</td>
<td>
\(\text{Na}_{2}\text{O}\)
</td>
<td>
\(\text{K}_{2}\text{O}\)
</td>
<td>
\(\text{Rb}_{2}\text{O}\)
</td>
<td>
\(\text{Cs}_{2}\text{O}\)
</td>
</tr>
<tr>
<td colspan="5">
Group 1 elements all form oxides in a 2:1 ratio
</td>
</tr>
<tr>
<td>
Atomic radius
</td>
<td colspan="5">
Increases as you move down the group.
</td>
</tr>
<tr>
<td>
First ionisation energy
</td>
<td colspan="5">
Decreases as you move down the group.
</td>
</tr>
<tr>
<td>
Electronegativity
</td>
<td colspan="5">
Decreases as you move down the group.
</td>
</tr>
<tr>
<td>
Melting and boiling point
</td>
<td colspan="5">
Decreases as you move down the group.
</td>
</tr>
<tr>
<td>
Density
</td>
<td colspan="5">
Increases as you move down the group.
</td>
</tr>
</tbody>
</table>
<div>
Table: Summary of the trends in group 1
</div>
</div>
</section>
<div class="ns-school-emp">
<h2>Optional Activity: Inventing your own periodic table</h2>
<div class="ns-school-defn">
You are the official chemist for the planet Zog. You have discovered all the same elements that we have here on Earth, but you don't have a periodic table. The citizens of Zog want to know how all these elements relate to each other. How would you invent the periodic table? Think about how you would organise the data that you have and what properties you would include. Do not simply copy Mendeleev's ideas, be creative and come up with some of your own. Research other forms of the periodic table and make one that makes sense to you. Present your ideas to your friends.
Circular periodic table
<img alt="" src="https://data.ulearngo.com/assets/130785b2-7093-41d2-ae45-3fcf3ba82066"/></div>
</div>

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Chemical Properties of the Groups

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 arrangement of elements and learn about materials, mixtures, pure substances, and separation techniques, including chemical formulae and important concepts such as periods in the periodic table and chemical properties of groups.


Chemical Properties of the Groups

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