<P> Each shell can contain only a fixed number of electrons : The first shell can hold up to two electrons , the second shell can hold up to eight ( 2 + 6 ) electrons , the third shell can hold up to 18 ( 2 + 6 + 10 ) and so on . The general formula is that the nth shell can in principle hold up to 2 ( n ) electrons . Since electrons are electrically attracted to the nucleus , an atom 's electrons will generally occupy outer shells only if the more inner shells have already been completely filled by other electrons . However , this is not a strict requirement : atoms may have two or even three incomplete outer shells . ( See Madelung rule for more details . ) For an explanation of why electrons exist in these shells see electron configuration . </P>
<P> Each shell can contain only a fixed number of electrons : The first shell can hold up to two electrons , the second shell can hold up to eight ( 2 + 6 ) electrons , the third shell can hold up to 18 ( 2 + 6 + 10 ) and so on . The general formula is that the nth shell can in principle hold up to 2 ( n ) electrons . Since electrons are electrically attracted to the nucleus , an atom 's electrons will generally occupy outer shells only if the more inner shells have already been completely filled by other electrons . However , this is not a strict requirement : atoms may have two or even three incomplete outer shells . ( See Madelung rule for more details . ) For an explanation of why electrons exist in these shells see electron configuration . </P>
how many electrons will go in the first shell of chlorine
how many electrons will go in the first shell of chlorine
two
two