00:01
In question a, we have to find the ground state electronic configuration of the lithium that has an atomic number of 3, of the sodium that has an atomic number of 11, and of the potassium that has an atomic number of 19.
00:16
Here on the screen on the left, i have drawn the order according to which we should allocate electrons in atoms.
00:25
So let's use this to find the electronic configuration of these three atoms.
00:31
First for the lithium, there are only three atoms to allocate, so two go to the 1s2 sub -shell, and the next one goes to the 2s1.
00:44
Now for the sodium, we have 11 electrons, so 1s2, the next sub -shell is 2s2, and then x1 is 2b6.
00:54
Notice that we already have 10 electrons, so there's only 1 to go, and it goes to the 3s1 subshell.
01:01
For the potassium, we have 1s1, 2s2, 2p6, 3s2, there are already 12 electrons...