atoms and nuclei summary

Summary - Dalton had postulated that matter is made up of atoms, which are indivisible. Thomson was the first to suggest a structure for an atom. According to him, an atom is a positively charged sphere of radius=10 - 1 0 m in which the mass and the positive ..

In the nineteenth century scientists saw enough evidence to prove that each element has its distinctive atom. But all tem atoms contain identical electrons. In spite of the fact that electrons carry negative charge, atoms as whole were found to be neutra..

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Introduction - In the nineteenth century scientists saw enough evidence to prove that each element has its distinctive atom. But all tem atoms contain identical electrons. In spite of the fact that electrons carry negative charge, atoms as whole were found to be neutra..

12. - The half-life of 92 U 238 against alpha decay is 4.5 x 109 years. How many disintegrations per second occur in 1 g of 92 U 238 ? Suggested solution: Again, since one k mole of any isotope contains Avogadro's number of atoms, there fore 1 g of 92 U 238 contains Half life T = 4.5 10 9..

01. - What is the distance of closest approach to the nucleus of an alpha particle which undergoes scattering by 180 o in the Gelger- Marsden experimen..

11. - If 200 MeV energy is released in the fission of a sample nucleus of 9 2 U 2 3 5 , how many fissions must occur per second to produce a power of 1 k..