Ytterbium, atomic number 70, is the first element in the Periodic table to have the first four shells full.

a) State the number of electrons in the fourth shell/ level of ytterbium (1)

b)How many orbitals are there in the third shell of ytterbium? (1)

Please help I'm very confused

1 answer

You have to go to the basics here. Do the electron configuration. The outer in Y is 5s25d1, before that {Kr}. So how many electrons in Kr?