Question

how to find out electronic configuration

Answer 1

You will be provided by atomic number . We just have to use is .In every atom there are shells they are name as K,L,M,N ,so on . we know the formula how the electrons are distributed in each shell 2n^2 .first shell has 2 electron second shell has 8 and third shell also has 8 .distribute .
like we have given find the electronic configuration of neon.so the atomic number of neon is 10. so electronic configuration would be 2,8.In same way u r given sodium so the electronic configuration would be 2,8,1 because it's atomic number is 11.