From Hydrogen to Tellurium - LITHIUM

Lithium

Lithium is the third element on the periodic table. It is not as famous as either hydrogen or helium so you might not have heard of it before. Being the third element, it has 3 electrons, 2 in the inner circle and one on its own in an outer orbit.

Lithium is quite happy to give away this outer electron and because of this scientists say that it is reactive. It gives away its outer electron to elements such as Hydrogen which need one additional electron to fill their outer shell of electrons. When a Lithium atom gives an electron to a hydrogen atom a new compound called Lithium Hydride is formed. There is no sharing of electrons involved. Scientists call this type of bonding ionic bonding.

I think of Lithium as being like a family with 3 children (electrons). The younger 2 are happy to stay near their parents (the nucleus). The older child or electron likes to go on sleepovers and often stays away for long periods of time.

The bonds in this type of compound are different to those discussed when we were talking about hydrogen joining with another hydrogen atom to make H2. In H2 both hydrogen atoms share the 2 electrons. Scientists call this a covalent bond.

The covalent bonds of Hydrogen remind me of 2 families with one child each living next door to each other. The children play together, moving from house to house, garden to garden. It is almost as if both families have 2 children.

Other elements which need one extra electron are Fluorine and Chlorine and these also form ionic bonds with lithium. We will be talking about these elements during weeks 9 and 17 respectively.

So what is Lithium like? Well, it is a metal and a solid, but unlike most metals it is very light - it is so light it can float on water. However if you put it on to water it will start to react - it will dart around and bubbles of hydrogen will be formed. As well as being very light it is soft and can be cut with strong scissors.

And its uses - the most common use for Lithium is in batteries.