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Dear Professionals UGC NET Solved Paper I, II, III available on  http://www.netugc.com/ UGC NET Paper I: Solved §   UGC NET Syllabus for Paper I §   2010 June UGC NET Previous Years Solved Paper I §   2011 June UGC NET Previous Years Solved Paper I §   2012 June UGC NET Previous Years Solved Paper I §   2012 December UGC NET Previous Years Solved Paper I §   2013 June UGC NET Previous Years Solved Paper I §   2013 September UGC NET Previous Years Solved Paper I §   UGC NET Paper II: Solved §   UGC NET Syllabus for Paper II §   2004 June UGC NET Previous Years Solved Paper II §   2005 June UGC NET Previous Years Solved Paper II §   2006 June UGC NET Previous Years Solved Paper II §   2006 December UGC NET Previous Years Solved Paper II §   2007 June UGC NET Previo

Q. Write two differences between isobars and isotopes. Ans:  Isobars           (i) Isobars have the same mass number but different atomic numbers (ii) Isobars have different  chemical properties Isotopes Isotopes have the same atomic number but different mass numbers. Isotopes have similar chemical properties. Q. Why do isotopes shows similar chemical properties. Ans: Due to same number of  electron  in valance shell Q. How Rutherford concluded that the center part of any atom not empty? Ans: When Rutherford experimented with  alpha particles , then he realized that few particles bounced back directly. Rutherford’s result lead him to believe that most of the foil was made of empty space, but had  extremely  small, dense lumps of matter inside, which is present only at the center because from center, few particles bounced back. All other particles deflected at different angles. So Rutherford concluded that the center part of any atom is nucleus not