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Nitrogen is the first element of group 15 of the periodic table and has the electronic configuration 1s2 2s2 2p3. Like oxygen and hydrogen, nitrogen exists in its elemental forms as a diatomic molecule. Nitrogen forms a variety of compounds in all oxidation states ranging from -3 to +5. The common oxidation states are -3, +3 and +5. Molecular nitrogen comprises 78% by volume of the atmosphere. Dinitrogen is a colourless, odourless, tasteless gas. It has two stable isotopes, 14N and 15N. It is non toxic. Dinitrogen is chemically unreactive a at ordinary temperature. At higher temperatures dinitrogen directly combines with some metals and nonmetals to form ionic and covalent nitrides. Some examples are 6Li + N2 --------> 2Li3N 3Mg + N2 --------> Mg3N2 In laboratory, dinitrogen is prepared by treating an aqueous solution of ammonium chloride with sodium nitrite. NH4Cl + NaNO2 -------> N2 + 2H2O + NaCl Uses of dinitrogen Dinitrogen is mainly used in the manufacture of ammonia and ...

Uranium is the last element occurring in nature. The elements coming after uranium are called transuranium elements. They are all synthetic in nature and are man made. They are radioactive and most of them have short half lives. For example :- 238 U 92 + 1 n 0 → 239 U 92 → 239 Np 93 + 0 e -1 Uranium → Neptunium 239 Np 93 → 239 Pu 94 + 0 e -1 Neptunium → Plutonium ( Here the Uranium(238,92) is abundant and non fissionable, It can be made into fissionable by reaction given above ) The element beyond actinides in the periodic table form atomic number 104 to 112 are called transactinide elements. These elements are rutherfordium (Rf), dubnium (Db), Seaborgium (Sg) etc. The nuclear reactions for the preparation of some of the transactinide elements are given below. 249 Cf 98 + 12 C 6 → 257 Rf 104 + 4 1 n 0 Californium → Rutherfordium 249 Cf 98 + 15 N 7 → 257 Db 104 + 4 1 n 0 Californium → Dubinium For more detail visit Indiastudychannel .com