Electrical conductivity The electrical conductivity decreases going across the Period 3 elements

Question 1

Going from Na to Al, there is an increase in the number of valence electrons that are donated to the ………….

Because of this, in Al….

Answer 1

‘sea’ of delocalised electrons

there are more electrons available to move around through the structure when it conducts electricity, making Al a better electrical conductor than Na

Question 2

Due to the giant molecular structure of Si, there are no ………. to conduct electricity

Answer 2

Due to the giant molecular structure of Si, there are no delocalised electrons that can freely move around within the structure
Si is therefore not a good electrical conductor and is classified as a semimetal (metalloid)

Question 3

Why are phosphorus and argon cant conducting electricity

Answer 3

The lack of delocalised electrons is also why P and S cannot conduct electricity

Question 4

Order of best conductor of electricity

Answer 4

AL-Mg-Na

Question 5

The SI unit of electrical conductivity is siemens per metre named after Ernest von Siemens.Previously, the unit used to be known as the mho, where not only is 1 mho the reciprocal of 1 ohm ( the unit of resistance), it is also ohm spelled backwards!