[jayanthd]

Somebody please explain Electronic Configuration in detail. I am confused about how the different shells or subshells fill. What is the rule for filling?

[Dan]

This is the kind of broad general question that textbooks are for - it is unlikely that anyone will be prepared to reproduce a chapter for you on an internet forum.

Try doing some background reading and come back with more specific questions, to which you should get a better response.

See Forum Rules:

Saying something like, "I don't get kinetics can you explain it to me" or "what is a Clausius-Clapeyron equation?" will get you negative responses on this forum. There is no reason to ask a question cold with the amount of information available everywhere on the web. First try to look it up – use google or wikipedia – and come here once you get to the point you don't understand something. Asking question without even trying to research it first is just a sign of laziness, nothing else.

[airplanet56]

First, be able to understand how to classify electrons with quantum numbers (e.g., n, l , ml, and ms).

Next, learn the order in which electrons fill orbitals. S subshells take 2 electrons, p take 6, d 10, and f 14. G, and h subshells are there, but you shouldn't worry about them. Look up where on the periodic table is the s block, p block, d block, and f block.

Know that it subshells fill in increasing n+l values.
The general order is 1s, 2s, 2p, 3s, 3p, 4s, 3d, etc. Notice how 4s comes before 3d because of n + l. If n + l is the same for two different subshells, you choose the one with the lower n value.

The ms quantum number is seen in the orbitals. In orbital diagrams, one electron is signified by an arrow pointing up, one down. They have opposite spins. Look up orbital diagrams.

This is a really broad question, you shouldn't ask them on a forum. However, here you go. Practice will make it perfect.