Question

The mass number of an element is twich its atomic number. If there are four electrons in 2p obitals, write the electronic configuration of the element and name it.

Answer 1

Since there are four electrons in 2p-orbitals, two electrons each must be present in 1s and 2s orbitals.
Therefore, the electronic configuration of the element is `: 1s^(2) 2s^(2)2p_(x)^(2)2p_(y)^(1)2p_(z)^(1)`.
The element with Z=8 is oxygen and its mass no. A=16.