What is tortoise shell?

What is the potential energy of an electron present in N- shell of the Be^(3+) ion ?

What is uricotelism ?In What way is it advantageous to the land animals which layed shelled eggs?

A small sphere of radius r_1 and charge q_1 is enclosed by a spherical shell of radius r_2 and charge q_2 . Show that if q_1 is positive, charge will necessarily flow from the sphere to the shell (when the two are connected by a wire) no matter what the charge q_2 on the shell is.

Which noble gas has less than 8 electrons in the valence shell of its atom ? What is this number ?

Which element has: Twice as many electrons in its second shell as in its first shell?

How many electrons are presents in the outer shell of carbon?

What is the maximum number of electrons present in an electronic shell ?