Question

A metal that does not act as a conductor of electric current is:
A. Sodium
B. Silver
C. Aluminium
D. None of these

Answer 1

Hint: Think about what properties an element must have to be considered a good conductor of electricity. Analyze the properties of the elements given in the options and decide whether they are good conductors of electricity or not.

Complete step by step answer:
Any substance that is considered to be a good conductor of electricity is considered to have free electrons or electrons that can be easily donated so that the electricity can flow. Elements that tend to donate electrons easily are considered to be good conductors of electricity. Almost all the elements in the s-block and d-block are considered to be good conductors of electricity since they tend to donate electrons as they are all metals. We know that metals donate electrons easily so they are good conductors of electricity.
Let us look at the atomic numbers of all the elements given in the options and determine whether they can be good conductors of electricity or not.

- Sodium: The atomic number of sodium is 11 and the electronic configuration is 2, 8, 1. So, it can lose one electron and achieve a stable octet. It tends to donate this electron and is thus a good conductor of electricity.

- Silver: The atomic number of silver is 47 and the electronic configuration is 2, 8, 18, 18, 1. To achieve a stable configuration, it has to donate one electron. This makes it a good conductor of electricity.

- Aluminium: The atomic number of aluminium is 13 and the electronic configuration is 2, 8, 3. Each atom is able to donate 3 electrons to achieve a stable octet and this makes aluminium a very good conductor of electricity.
Hence, from this we can conclude that all the given options are good conductors of electricity .
So, the correct answer is “Option D”.

Note: Note that aluminium can achieve a stable state of configuration by donating just one electron too. This is due to the presence of sub-orbitals and if it loses one electron then a stable state can be attained as one of the sub-orbitals will be completely filled and the other two will be completely empty.