Groups in the Periodic table

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ALKALI METALS

Alkali metals are group one metals found on the far left column of the periodic table.

Includes Lithium, Sodium, Potassium, Rubidium and Caesium.

Some of the most reactive metals in the world. They share properties with some metals but also have some distinct properties

Good thermal and electrical conductors. Also very shiny but since they are very reactive they tarnish in air quickly, this is oxidation to form a metal oxide. To prevent oxidation they are stored under oil.

When they react with other compounds they give away 1 electron. They form ions and bond with ionic bonding.

Not strong or hard wearing. Very soft and can be cut by a knife. Lithium is hardest in the group but can still be cut. They become softer as you go down the group.

Have quite low melting points for metals. Melting point of Lithium at 180 degrees Celsius. Caesium can melt at body temperature.

Have low density. Lithium, potassium and sodium can float on water.

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REACTIVITY IN GROUP 1

Lithium fizzes and produces gas when reacted with water. It produces hydrogen which can be tested for using a lit splint to hear a squeaky pop.

Sodium reacts similarly to Lithium but produces hydrogen more quickly and becomes hot enough to melt the sodium. Turns water into an alkali with NaOH.

Potassium with water ignites producing a lilac coloured flame.

As you move down the group the reactivity of the element increases.

As the electrons become bigger, they get more electron shells therefore the electron they want to lose is further away from the nucleus and isn't held as tightly. Lithium has few outer shells so losing an electron is more difficult than caesium which has a lot more outer shells.

React readily with the Halogens