Periodic Table of the Elements
Alkali metals make up the first group of the periodic table.
Hydrogen IS NOT part of the family.
Alkali metals are shiny soft metals that oxide with the dioxygen from the air.
More impressive, they react strongly with water. The reaction in exothermic, meaning that the reaction is releasing energy. The energy released can be enough to produce a flame.
The bigger the atom, the more reactive the element is because the valency electron is easier to be snatched.
explanation on the reactivity:
Alkaline Earth Metals
Alkaline earth metals make up the second group of the periodic table.
These metals also react with water, though not as vigorously as the first group.
Because they possess the properties of metals, the transition elements are also known as the transition metals.
The transition metals are placed in the center of the periodic table, between groups II and III.
- dense and shiny
- forms coloured compounds
- good conductors of heat and electricity
- malleable and can be hammered or bent into shape easily
- high melting point (exception of mercury)
- forms positive ions and basic oxides
The halogens are five non-metallic elements found in group VII of the periodic table. The term "halogen" means "salt-former".
In an atomic description, they are all just one electron shy of having full shell. Because they are so close to being happy, they have the trait of combining with many different elements. They are very reactive. Reactivity decreases as you move down the column.
They form diatomic molecules in the pure state. The halogens are poisonous, and chlorine gas and chlorine compounds have been used as chemical weapons.
Noble gases form the group 0.
they are all odorless, colorless, monoatomic gases, with (almost) no reactivity.
The properties of the noble gases can be well explained by their atomic structure: their outer shell of valency electrons is full,and happy atoms have full shells.Therefore they don't need to bound to catch/release electrons (e.g react) to become stable.
Noble gases are commonly used in lighting because of their lack of chemical reactivity.