Two electrons in the same atom that have identical values of the quantum numbers n, l, and ml are said to be in

The four quantum numbers are n, l and ml, and ms.

The first three of them describe the orbital on which the electron of an atom is.

n is the main quantum number and it represents the shell. This is also the row (period) on the periodic table.

l is the orbital angular momentum number and it tells the shape of the orbital. It may be

0 which is s orbital

1 is p orbital

2 is d orbital

3 is f orbital

ml is the the magnetic quantum number: It gives the position of the orbital in the space.

Those three quantum numbers, n, l, and ml, then, determine the orbital.

The fourth quantum number, ms, is the spin.

Answer: the two electrons with the same n, l, and ml quantum numbers are said to be in the same orbital.