(a) Lithium, sodium, potassium are all metals that react with water to liberate hydrogen gas. Is there any similarily in the atoms of these elements ?
(b) Helium is an unreactive gas and neon is a gas of extremely low reactivity. What, if anything. do there atoms have in common ?

Oxidation number is the charge which an atom of an element has in its ion or appears to have when present in the combined state. It is also called oxidation state. Oxidation number of any atom in the elementary state is zero. Oxidation number of a monoatomic ion is equal to the charge on it. In compounds of metals with non metals, metals have positive oxidation number while non metals have negative oxidation numbers. In compounds of two difference elements, the more electronegative element has negative oxidation number whereas the other has positive oxidation number. In complex ions, the sum of the oxidation number of all the atoms is equal to the charge on the ion. If a compound contains two or more atoms of the same element, they may have same or different oxidation states according as their chemical bonding is same or different. Oxidation number of sodium in sodium amalgam is

According to Avogadro law the correct statements are a) Volume of gas is proportional to the no. of moles at constant T and P b) The pressure of a gas is directly proportional to temp. of the gas under all conditions c) Equal volumes of different gases under similar conditions consist of equal no. of molecules d) Equal volumes of different gases under same conditions have equal no. of atoms

In the modern periodic table, the elements are placed in order to increasing atomic number. These have been numerous designs of the table over the years but the most common is the long form of periodic table. The long form of periodic table shows all the elements in numerical order. What is the atomic number of the (as yet undiscovered) alkali earth metal after radium?

Two gaes A and B are contained in two separate, but otherwise identical containers. Gas A consists of monatomic molecules, each with atomic mass of 4u whereas Gas B consists of rigid diatomic molecules, each with atomic mass of 20 u, If gas A is kept at 27^(@)C , at what temperature should gas B be kept so that both have the same rms speed ?