Group 0
group 0The vertical column of non-metal elements on the far right of the periodic table, also called the noble gases. contains non-metalElement that is a poor conductor of electricity and heat, and which forms acidic oxides. elementA substance made of one type of atom only. placed in the vertical column on the far right of the periodic tableA tabular representation of all known elements in order based on atomic number, eg all the noble gases are found on the right of the periodic table.. The elements in group 0 are called the noble gasesThe elements in group 0 of the periodic table, named for their lack of chemical reactivity.. They exist as single atomThe smallest part of an element that can exist..
The noble gases show trends in their physical propertiesA description of the appearance of a substance or how it acts without involving chemical reactions. For example, state, melting point, conductivity, etc..
Learn more on groups in the periodic table in this podcast.
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Boiling points
The noble gases all have low boiling pointThe temperature at which a substance rapidly changes from a liquid to a gas.:
- helium, at the top of group 0, has the lowest boiling point of any element
- boiling point increases going down the group
This is because, going down group 0:
- the atoms become larger
- the intermolecular forcesWeak attractive forces between molecules. When a simple molecular substance melts or boils, it is the intermolecular forces that are broken (not the covalent bonds in each molecule). between the atoms become stronger
- more energyThe capacity of a system to do work or the quantity required for mechanical work to take place. Measured in joules (J). For example, a man transfers 100 J of energy when moving a wheelbarrow. is needed to overcome these forces
Question
Radon is situated below xenon in group 0. Predict the likely boiling point of radon.
The actual boiling point of radon is -61.7藲C. An estimate would lie midway between -100藲C and -50藲C based on the shape of the graph.
Compared to other elementA substance made of one type of atom only., the noble gases are very unreactiveA substance is unreactive or inert if it does not easily take part in chemical reactions. - they do not take part in chemical reactions.
Explaining the inertness of noble gases
The table shows the electronic structureA set of numbers to show how the electrons in an atom are arranged in shells, or energy levels. of some noble gases. All the noble gases have complete outer shells:
- helium has only two electrons
- the other elements have eight electrons in the outer shell
Element | Electronic structure |
Helium | 2 |
Neon | 2,8 |
Argon | 2,8,8 |
Element | Helium |
---|---|
Electronic structure | 2 |
Element | Neon |
---|---|
Electronic structure | 2,8 |
Element | Argon |
---|---|
Electronic structure | 2,8,8 |
When elements react, their atoms complete their outer shells by losing, gaining, or sharing electronSubatomic particle, with a negative charge and a negligible mass relative to protons and neutrons.. Atoms of group 0 elements already have stable arrangements of electrons. This means that they have no tendency to lose, gain, or share electrons. This is why the noble gases are unreactive. It also explains why atoms of group 0 elements do not share electrons to form molecules.