Answer:
where is the drawing? I can't help if I can't see it sorry
The element symbol in chemistry comprises atomic number and mass number.
Atomic number is written on the top of element and mass number is written at the bottom.
For eg:
If Y is an element that is having atomic number a and mass number x. Then its denotion will be:
ᵃYₓ.
So here ⁹F₁₈.₉₉
Here 18.99 will denote mass number while 9 will denote atomic number.
To calculate an electron configuration, divide the periodic table into sections to represent the atomic orbitals, the regions where electrons are contained. Groups one and two are the s-block, three through 12 represent the d-block, 13 to 18 are the p-block and the two rows at the bottom are the f-block.