Hybridization General Question

[CNourian2H]

In Homework question 2.45, it asks to write the hybridization of each lone pair in the bonding in H2C =(double bond) CHCHO. The drawing in the answer key says the lone pairs of O have a hybridization of sp2 but the hybridization of O when its bonded is 2sp2 (difference is the 2 in front). What does this 2 represent? I'm very confused how to determine if i need to put that 2/# or not.

[nicolely2F]

2 stands for the energy level in which the hybridized orbitals are located. I think they're only necessary when writing bond hybridization. The number is associated with the element's period in the periodic table.

[Sears 4A]

do we need to put the energy level into our answers when we write down hybridized orbitals?

[nicolely2F]

do we need to put the energy level into our answers when we write down hybridized orbitals?

Can't say for sure but probably not... I only see them in bonds in the book.