Periodic Table

Alkali Metals React with Chlorine All alkali metals react with chlorine gas to form white metal chlorides salt.Group 1 Metals + Chlorine Gas → Metal Chloride The metal chlorides salt formed is soluble in water to give a neutral solution of pH 7. The reactivity increases down the group from lithium, sodium to potassium. Example: … Read more

Chemical Properties of Alkali Metals Group 1 metals are very reactive metals. They all show the same chemical properties. They can react with water and non-metal such as oxygen and chlorine to form a new compound. The table to the right shows the electron arrangement of all the Group 1 metals. All the atoms of … Read more

Physical Properties of Alkali Metals Name Proton number Electron arrangement Lithium 3 2.1 Sodium 11 2.8.1 Potassium 19 2.8.8.1 Rubidium 37 2.8.18.8.1 Caesium 55 2.8.18.18.8.1 Francium 87 2.8.18.32.18.8.1 All Group 1 metal exist as solid at room temperature and hence have all the typical metallic properties, such as: good conductors of heat good conductors of … Read more

The Group 1 metals is called the Alkali Metals. This is because they form oxides and hydroxides that dissolve in water to give alkaline solutions. As shown in the diagram on the right, elements in this group are lithium, sodium, potassium, rubidium, caesium and francium. They are the first element of a period, with one … Read more

Uses of the Group 18 Elements Helium Airship The gas is much less dense than air. Therefore it is used in balloons and ‘airships’. Because of its inertness, it doesn’t burn in air, UNLIKE hydrogen which used to be used in large balloons with ‘flammable’ consequences. Deep-sea Diving Helium is also used in gas mixtures … Read more

The “Noble Gases” are the last group in the Periodic Table, they also known as “inert gas”, due to their non-reactive behavior. This group consist of six elements, namely Helium, Neon, Argon, Kripton, Xenon and Radon. They are non-metallic, colourless gases at room temperature and pressure with very low melting points and boiling points. They … Read more

Periodic Table and Electrons Arrangement The classification of Group and Period are totally related to the electron arrangement of the atoms. As shown in the table above, the classification of elements in a periodic table is as follows: All the elements in the same group have an equal number of valence electron(s) (outer most electron) … Read more

Modern Periodic Table In the modern periodic table, the elements are arranged in ascending order of proton number. The vertical columns of the periodic table are called GROUPs whereas the horizontal rows are called the PERIODs. Group The vertical columns of the periodic table are called Group. There are 18 groups in the periodic table. … Read more

History of Development Johann Dobereiner – Law of Triads Nature contained triads of elements The middle element had properties that were an average of the other two members when ordered by the atomic weight (the Law of Triads). John Newlands – Law of Octaves Any given element will show similar behavior to the eighth element … Read more

Revision Notes 4.1 The Periodic Table4.2 Group 18 Elements 4.3 Group 1 Elements4.4 Group 17 Elements4.5 The Periods and Transition Metals Videos The Group in Periodic Table The Period in Periodic Table Group 18 Elements Group 1 Metal Reaction of Alkali Metals with Oxygen Gas Group 17 Elements Reactivity of Group 17 Elements