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    | • | An atom is
    composed of 
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    | • | The _________
    (positively charged) and _______ 
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    |  | (uncharged) are
    found in a very small, dense 
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    |  | portion of the
    atom called the nucleus . 
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    | • | __________
    (negatively charged) surround the 
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    |  | nucleus in a very
    diffuse region and have a much 
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    |  | 
   
    |  | smaller mass than
    the proton and neutron. 
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