Periodic Table
By: Cody Radmeaker
Metaloids
Have a metallic appearance, but they are brittle and only fair conductors of electricity.
Other Nonmetals
They largely exist as monotonic gases, with a few having more substantial diatomic or polyatomic forms unlike metals.
Hablogens
They are highly reactive, and as such can be harmful or lethal to living organisms in scientific quantities.
Noble Gases
Noble gases are typically highly unreactive except when under particular extreme conditions. The inertness of noble gases makes them very suitable in applications where reactions are not wanted.
Post-Transition Metals
Physically, post-transition metals are soft (or brittle), have poor mechanical strength, and melting points lower than those of the transition metals; most also have boiling points lower than those of the transition metals.
Transistion Metals
None.
Actinoids
- All are radioactive.
- Actinides are highly electropositive.
- The metals tarnish readily in air.
- Actinides are very dense metals with distinctive structures. Numerous allotropes may be formed (plutonium has at least 6 allotropes!).
- They react with boiling water or dilute acid to release hydrogen gas.
Lanthanoids
- Silvery-white metals that tarnish when exposed to air, forming their oxides.
- Relatively soft metals. Hardness increases somewhat with higher atomic number.
- Moving from left to right across the period (increasing atomic number), the radius of each lanthanide 3+ ion steadily decreases. This is referred to as 'lanthanide contraction'.
- High melting points and boiling points.
- Very reactive.
- React with water to liberate hydrogen (H2), slowly in cold/quickly upon heating. Lanthanides commonly bind to water.
- React with H+ (dilute acid) to release H2 (rapidly at room temperature).
- React in an exothermic reaction with H2.
- Burn easily in air.
- They are strong reducing agents.
- Their compounds are generally ionic.
- At elevated temperatures, many rare earths ignite and burn vigorously.
- Most rare earth compounds are strongly paramagnetic.
- Many rare earth compounds fluoresce strongly under ultraviolet light.
- Lanthanide ions tend to be pale colors, resulting from weak, narrow, forbidden f x f optical transitions.
- The magnetic moments of the lanthanide and iron ions oppose each other.
- The lanthanides react readily with most nonmetals and form binaries on heating with most nonmetals.
- The coordination numbers of lanthanides are high (greater than 6; usually 8 or 9 or as high as 12).
Alkaline Earth Metals
- An oxidation number of +2 which makes them very reactive.
- Not found freely in nature.
- Present in the earth's crust but not in their basic form.
- Distributed in rock structure.
- Two electrons in their outer shell.
- High boiling points.
- High melting points.
- Low density.
Alkali Metals
They have low melting and boiling points compared to most other metals. they are very soft and can be cut easily with a knife. they have low densities (lithium, sodium and potassium will float on water)