किन कणों को किसी परमाणु के नाभिक में उसके रासायनिक गुणों को बदले बिना जोड़ा जा सकता है?

The table below shows information about three elements X, Y, and Z. Some values are missing and are represented by l, m, and n. ElementAtomic numberMass numberNumber of neutronsX1123lY1735mZn4020 The values of l, m, and n are respectively:

The maximum number of electrons that can be accommodated in the third shell (M shell) of an atom is: